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Currently I have a mostly stock 2001 Dodge 2500 with an auto tranny (sadly). It has stock injectors (probably original) and a rebuilt hy35 turbo and 5 inch straight pipe exhaust. No stud, no major mods. Have a quadzilla tuner and running a pretty mild tune off it and im trying to go for lower egts. Eventually id like to make 350ish HP and thats about it. It tows regularly 3k to 14k constantly and and does pretty decent at it... Until egts start getting around 1200F. Im trying to find a common Proven setup that works for this application. I do plan on putting an exhaust brake on it at some point and would like to try to steer away from having 2 turbo's and keep it simple. Any suggestions?

Can someone please tell me what transmission I have? Trying to troubleshoot why I don't have overdrive. And well... Sure help to know. All I know is that it's not the original transmission AND the previous owner (for whatever reason) put in a resistor (1kohm) between (looks like) the temperature wire and a ground. Below are the numbers I found on the transmission. And thanks in advance for y'alls help. (First time forum post). Number above pan, driver side. PK52118320 2016 3230 Number by gear box, passenger side. 283-2 Pic of pan

No boost and 100% transmission slip???? So I just changed my oil and fuel filters along with fixing an oil leak on the vacuum pump. To fixing the oil leak I unplugged the sensor behind the vacuum pump and the three wire plug next to the engine ID plate..... fixed the oil leak and re-assembled everything. While I was drive home, I noticed it not registering boost and the trans was at 100% slip. I foot braked it to try and build some boost. It start to build up but felt like it just fell on its face and didn't have any power. Still drove okay I tried resetting the app sensor no change. 01 2nd gen, BT iquad all the normal mods. Looking for ideas?!

So I want going to start putting my case back together today, and I thought I should check out the low roller clutch cam (race) pressed into the case. I noticed some discoloration on the it. Looks like heat, but also pretty localized to a small area. I put my hand in it and noticed it wiggled a little... Not good. So I pounded it out, and I can see it spun off its teeth. Now what? I've read about bolt-in replacements. I'm over 1000 lbft of torque. What are my options? I'm going to do some more research on this but I'd like to know if there's any first hand knowledge around here for this problem. Pictures below. Thanks in advance!

I'm stuck on a topic that I see a lot on 2nd gens, especially moving up in horsepower. Beef up the transmission, upgrade the tranny, etc. What is the most practical option to do this? I'm looking to get to the 500hp range. Suggestions? Thanks in advance!

O k fellows i have a 2005 170.000 miles transmission works fine but thinking of pre maintance we travel construction i pull 16.000 lb rv worry about breaking down on the road i no there several places to get a trans but I'm concerned about a warranty . also thought about upgrade vb and tc and drive it or just drive it. So if a person does what i do to make a living thoughts on best thing to do with it i drive the truck little bit but pull rv couple times a year located now in raleigh nc

Getting the money together to finally get the manual trans for the project. I know a NV4500 is a pretty easy swap out as it was stock, and I've been in contacts with high-impact.net for the parts. I know the NV5600 entails a bit more of a challenge (a poster had a link to a thread of someone else's swap) so that CAN be done. But I was wondering if anyone has grafted a G56 to a 12 valve 6bt?

Good afternoon everyone, forum newbie here. Looking for help with an issue on my 2001 5.9 Automatic. I've owned this truck for a couple of years now and had various issues fixed. But one that I can not get fixed is a complete lack of power towing. I have a 27ft 5th wheel thats only ~8000 Lbs. The truck alone with me and my passengers / family weighs 7980. So, I'm just around 16,000. Going down the highway, especially starting up any grades I rapidly loose speed. I've towed as long as I have been driving with other rigs and know that when you loose momentum its likely not coming back. But to the point... Even on flat ground or a 1% grade, around 65MPH, my choices are OD locked out and almost 3000RPM or OD on and 2000RPM, the 2000 though is the MAX, it will not go past that. While doing research I found TSB 18-024-00 which talks about an issue almost identical to what I am experiencing (my engine is in the date and serial number ranges mentioned). Armed with this knowledge I went to the dealer to have them flash the relevant parts to fix this issue. The technician stated the computers were already at the latest software and there was nothing they could do for me. But happily charged me. I didn't believe them so I argued and went back stating "I asked you to flash it, just flash it" he said "Its the latest version so the computer wont let me flash them" The only things that came of this interaction were getting the 3cyl/high idle software enabled. The technician continued to state "This is a California truck, we can sell you an Idaho truck, brand new"... NO! I've done tons of searching and can't find if there are any differences between CA and Non-CA for 2001, I know all the new trucks are the same due to the new emissions controls. I know I have the issue mentioned in the TSB, is there somewhere other than a dealer that I can get my computer force-flashed to the latest software to fix the TSB? (Without buying EFI Live or Smarty) ? The other claim by the technician was to just use the Edge Juice w/Attitude CTS2 that I had installed in the truck to override it and that it would not hurt the engine or the transmission. I had originally only installed it for the gauges (best PID coverage for the money at the time), but it came with the tuning features for only $100 difference, I originally had no intention of using them. I want my truck to be able to tow in mode 0 (stock-ish) without pushing it. But yes, surprisingly, changing to even mode 1 immediately breaks the 2000RPM limit. Lift PSI is 5 to 7 at this time. Extra info: Things I've fixed: Torque converter surging due to misplaced ground. Stock replacement fuel pump (bad decision I know) Things I've upgraded: BHAF. Edge Juice CTS2 Things I'm trying to fix: The Limit noted in this post (Lack of Power), Low boost / excessive black smoke even on stock mode... need to build the tester. Things I'm wanting to upgrade: Injectors, I read and hear a lot of opinions here +50, +75... I want fuel economy,and power, not trying to hot-rod this, its a tow vehicle. Fuel Pump.. Ive heard good and bad about many brands and am caught up in a brand war here in Boise, one dealer of both FASS and AirDog said they've pulled AirDogs out of the box that didn't work and can't get them warrantied even before install. The other dealer of both says the same about the opposite brand. My friends who's owned these and is a mechanic, but not diesel said just to go with the in-tank conversion and not an expensive setup...

So after hauling home a new 5th wheel project today, I noticed that my new transmission gauge seemed inop. I tore down the dash and found the tap splice I used may have had an intermittent connection ( I hate those things) so I switched out a butt connector and that seemed to fix it. As I was there putting the dash back together, I figured I'd check the trouble codes for fun. It spit out the following: P0622 P0743 P1693 P1765 Now I had noticed wayyy back in fall that the trans had shifted in and out of OD on the highway a few times on a few separate days but quit. I have since then installed a lockup switch on the dash. Would the lockup switch cause the codes because you are messing with the transmission signals- so to speak? I did test the alternator with my MM and got .01- .02 VAC, not alarming. I also read the trouble code trouble shooter on the info pages, but I don't have a scan tool that can freeze frame and what not. Could it be my 3 day old EZ causing this? I don't know how long these codes were present. Any thoughts?

I am just curious as to what upgrades can support around what hp inrease. To my understanding doing just torque converter and valve body would be ok for a little more hp over stock but does anyone know about how much? Also, adding on the input and output shafts, how much more can you then add? My goal for now is a Smarty tuner and 75 horse injectors.

I've noticed a vibration in 6th gear on the highway in my '02 HO CTD. If I am gradually accelerating, the vibration begins at 72 mph, and continues on up through 80 mph (I haven't been up much higher). But if I am on the pedal, the vibration will begin as soon as I hit 6th at around 55 mph or so. The vibration feels like it's coming from the rear half the truck (I can't feel much of it in the steering wheel, but a little shake is there). Around town at lower speeds and in 1st-5th it drives smooth. I haven't heard any noises coming from the drivetrain either. Has anyone experienced this same symptom? Or have thoughts on the source? Maybe a wearing u-joint? The tires are freshly mounted and balanced, and the truck was aligned last week. If engine RPM at these speeds would help, I can go check and reply. Thanks!!

Well it has come time to rebuild my transmission. Ive recently replaced the governor solenoid and sensor, adjusted bands and replaced filter and fluids. Well now it is not down shifting. The forward band is worn beyond use, and I'm sure that with the shifting issues I've experienced over the last two year that the rest of the internal works are worn just as bad. Ive adjusted bands, changed fluid and filter, adjuster TV cable, replaced solenoid and sensor, and still no improvement. So it is just worn out, closing in on 200,000 miles with a stock tranny, I can't complain. :lol:So I'm doing the Sun Coast M3GA 3 Alto Transmission Kit, Sun COast Triple Disc Torque Converter, Sun Coast Billet FLex Plate/Fly Wheel, ARP Fly Wheel bolt upgrade, Sun Coast's governor solenoid upgrade it with housing, and Mag-Hytec 727 D Deep Dish Pan. What else should I change while in there? The rebuild kit from Sun Coast comes with every thing internal including shift kit for the valve body. But are there other parts I should do while Ive got the tranny on the bench, either to the truck or transmission. I am gonna replace the TV cable also as it is fraying up at the throttle connection. Thank guys.

SO it seems to be one thing after another with this truck. First the batteries kept going dead due to a grid heater solenoid sticking open, then my fuel pump went, now my trans wont shift out of neutral. All in about a 3 week span.I just finished installing my new AirDog II, bled the system and fired the truck up. Went to put it in reverse, heard the engine load down like it normally does but nothing happen. Went back to park and heard a slight grinding. Put it in drive, same thing, I hear the load but no movement. Put it back in park and a lot of grinding, had to move back to reverse then park top make it stop. Turned the truck off, I can roll the truck in any gear, Park, Reverse doesn't matter.What is/could be going on here? Any help is greatly appreciated.

Well, joined the forum back in Nov... had been working on plotting out our tune up/ preventative & maintenance plans and before we got anywhere within driving the truck an additional 500 miles at most we have MAJOR ISSUES... needless to say we have have the truck parked in the driveway since we put new tires on it at the end of November, we have had to start it a few times to move it for snow removal and driveway access issues... So here goes the saga of problems... this fall we noticed that we were having issues with the truck shifting around 45 mph... after much reading on this forum, I do believe that it probably is the same torque lock/ converter issue that many have been having. So, I had been calling around to different auto part stores to research alternators as a place to start... My husband also informed me that I was not the only one who had replaced the batteries in the truck in the last year or so (It would have been nice if he would have told me that a little sooner, since I am the more mechanical of us)... We had also been fighting with the 4wd for about a year... The mechanic that we were using supposedly replaced some of the parts but I do not know which ones bc he did not record it in the system and we had issues with the other work that he said he had done at the time but upon closer inspection did not do. My brother and I traced all the vacuum lines and made sure none of them were dirty/clogged/ disconnected etc.. one or two of them were dislodged/ loose so we cleaned them made sure they weren't clogged and reattached them . We also checked the diaphragm and it seemed to move in/ out easily as well... but we did not have time to get any further in diagnosing, before many more issues started to arise... My husband had a training seminar in Denver and we knew we needed new tires so we were able to combine the trip, I didn't have time before he left to change the oil so he insisted on going to a grease monkey as well while he was down there... then literally as my husband was driving home from Denver which is about an 1 hr 30 min drive up a mountain pass; a slue of other issues started... Unfortunately I wasn't in the truck at the time and my husband is not the best at paying attention to subtle vehicle noise/ performance differences. TO all the guys out there, I love my husband very much and in no way am I trying to "dis" him, we have just been together long enough that we both recognize each others strengths and weaknesses... so back to the drive back home per my husband's account; he called me and says "Sarah I think something is wrong with the truck, if I accelerate past about 60 the vehicle will not shift, just revs highier and higher and I have never seen the rpm gauge go so high..." My reaction was, well SLOW DOWN, if it;'s not shifting it's not going to just because u give it more fuel and rev the engine. Secondly, I asked him to check the temp gauge (unfortunately, we have not installed additional gauges that I had already ordered.. so we still just have stock) and make sure that he didn't need to pull over... he responded with well I am not sure what it's normally at but it doesn't seem unusually high. Well, how about the other gears? It was sluggish to get started, even when it was warmed up... So, when he got home we parked the truck and the next day I took it out to drive it to see if I could get a better feel for what was going on. First off, the truck wouldn't start... it had been cold that night probably around -10, but the truck block heater was plugged in and when I went to drive it the temp had already warmed up to around 30... when it gets that cold I have found that the truck will usually start easier if I turn the key and wait for the "wait to start" light to turn off two or three times before actually cranking the engine. However, even with this technique (which I realize is a red flag in itself) the truck would click click click try to turn over and just wouldn't go... so I got out the trust battery charger and usually if I just put it on high for less than 5 mins the truck will start right away... no such luck... so I left the charger on for about 30 mins before it would start (when it did there was quite a bit of smoke, although I don;t remember if it was black or white). Once started, the truck idle was very slow (even more than usual) so instead of going inside, I sat in the cab and rev'ed the engine for the concern of gumming etc. It took about 5 mins before I felt comfortable to let the truck sit and run while I wasn't watching it... I let it run for about 10-15 mins before I got in for the test drive. I immediately noticed that when backing up that the truck was acting very sluggish...we live right on main st in our town which is actually a HWY, so we have quite a bit of traffic and pulling out you have to be careful and quick... Which is why I panicked when I shifted into D, hit the accelerator and the truck acted like I merely let off the brake and barely pressed the accelerator, when in reality I nearly floored it. luckily we have a second lane & parking shoulder that starts at our driveway and goes through town, so I was able to creep into it... about 2 blocks of creeping with medium pressure on the accelerator the truck seemed to kick into gear and started to accelerate more normally between about 20-55mph then I did notice that once I reached 60mph I could understand what my husband was experiencing the day prior. After driving just to the next lil town which is 1.5 miles away and back I parked the truck... called our friend that is a mechanic and just started working at the garage literally across the street from our house and started reading... Our mechanic friend said he would help us out after work at the garage (so awesome to have access to the lifts & tools)... but before we could look at the truck our other vehicle decided to have a few issues that we needed to address first (so we would have a vehicle to use), we were able to plug in the code reader and at first no codes were coming up... then we had one or two codes pop up but when he looked them up there were a slue of possibilities and I lost my notebook where I wrote them down, ugg... i blame the chaos on the holidays... We decided that a good place to start would be to change the trans solenoids, replace trans filter w/ seal kit, flush trans and new fluid. Which we were planning on doing tomorrow... in preparation for finally tackling this truck I have been reading, researching and pricing a plan of action this week. Yesterday I did order a TIMBO apps, since it was something that I was thinking about anyway... but I am just getting a little overwhelmed with what parts to address especially with the current issues that I think are somewhat inner related and I fear we will have more issues as I have read through the forum bc we have had above average luck with not needing many of the issues that people have had with this truck at much lower mileages we are at about 203k... So, I need some advice... Gauges- I want basic mechanical gauges in a pillar (EGT, fuel pressure w/ low pressure light, trans temp)... I tried to order some in NOV but had problems finding a matching set, that was reasonably priced but had good reviews (quality). It shouldn't be that difficult... so if anyone has bought them recently and has a source suggestion, please let me know! AirDog II- What do I need to order in addition to the Airdog II to install on truck? Our truck specs are on signature.. Fuel Pump- Raptor: Which model? the factory replacement (FRRP)? RP-100 or RP-150? From what I have been reading and knowing that we use the truck to tow our tool trailer & our flat bed trailer, as well as hauling all sorts of other stuff up and down mountain dirt roads, I was thinking that it would be a better idea to install the RP-100 and take the time to mount it rather than just doing the factory replacement. Any Thoughts? Automatic Transmission: What do you recommend to do while we are in there replacing the solenoids, flushing, replacing filter & kit, new fluid... adjusting bands... WHAT ELSE CAN I DO TO PROLONG THE LIFE OF THE TRANS/ fix issues? Or should I be considering a total rebuild or new one? (I am hoping that I can prolong the current one so I can budget some other stuff first)- If we do replace, I think we may convert to a manual trans set up.... Sorry this is SUCH A NOVEL, I just thought I would give as much detail as possible since I am out of my comfort zone... THANK you in advance for any help/ suggestions you can provide! At this point we need 2wd to work before 4wd!!

The new truck I bought (2002 in sig) turns out to have a bit different trans than the seller advertised... I still would have bought the truck, but I need to make some changes. The trans was the only non stock part I couldn't verify before the quick sale the guy needed.The trans was supposed to be a BD torque converter, billet input, street/towing valve body, and sun coast guts. I did some hunting and found the shop that did the trans. The builder was a good guy and honest with me. He also let me know that his 3 year 36k mi warranty also applied to me, since he knows the truck. What I got was a hardened cryo treated input shaft, CVC stock replacement converter, good set of clutches/bands, and a mild hand modified valve body. I discussed the options with him in making the trans a bit more sturdy so I don't burn out anything prematurely. He offered a CVC single clutch billet converter that CVC rated at 1200 ft/lbs and a moderately worked street / strip valvebody for $600, and since he did the trans, he said he would keep the stock CVC converter for a $120 core, totaling $480. I am seeing a peak of 48 or so psi of boost when I roll on the throttle, and I want something that I could still tow some with, but something that will still run through the gears fairly well without burning out at either. I am thinking of taking him up on the deal, as the hardened input should be good for what I need and if the rest of the internals are okay I should be in good shape to drive and occasionally tow.As I've mentioned... I know little about automatics. What do you guys think?

I know this conversation has been around forever, but while asking people what to tow my 5th in, I get about a 50/50 split on answers, so I am asking here.I have a 2001 Dodge Cummins, Quad Cab 4x4 with the 3.54 ratio. Only mod's to the motor are the SuperChip set to "tow-safe mode" and a K&N air filter. My 5th weights about #9500 and I dont tow my 5th under 55mph with OD. My problem comes in when I hit the interstate and run 65mph. My motor will scream if I leave it in Drive.What is the correct towing procedure??????

this weekend i am taking my tranny out and preparing to install another one next week end. i have read several write ups here and feel confident i can do this. i know the nv5600 is quite heavy and i am prepared for that. just how heavy is the transfer case? i dont want ot get clobbered by it either.i figured while I had it out i would replace the seals since they leak slightly. does a seal removal tool make the job any easier? i have seen other ways, but if the tool is worth spending the money on i am all for it. any advice is appreciated.

i have posted before about my 6 speed and it jumping out of 1st, rev, and 6th. today i was coming home and went to shift for m 4th to 5th and it stuck in 4th. it did shift into 5th but it took some effort to get it out. it now no longer will go into 4th. it pulls into the position but does not engage the gears. 3rd is clashing just a wee bit but working fine while in gear. it never made any noises just stuck ther in fourth until i forced it out. i am sure i have to either rebuild or replace the tranny. i have had a hard time finding any one who wants to work on that six speed. i know some of you out there have 6 speeds and i was hoping you have had some good experiance with any of the many remanufacturers out there. or maybe some has one laying around they might want to get rid of. i also want ot know if any one has any opinions on wether they would drive this thing or park it before i have a catasrophic failure.

Does anybody know of a thread on adjusting the TV cable from the APPS to the trans. for Auto trans?? Richie

I am looking at both but the Fast Coolers are $125 vs. $239.95 for the Trans-Coolers. Anyone one using these. I would appreciate hearing about how both of these work, your likes and dislikes, and recommendations. Thanks!

I've spent the better part of a day an a half searching for someone that has posted something similar to the problems that I am having with no avail. I am hoping someone has some insight. This is on my 2001 4X4 that is pretty much stock.Background - It is on the third engine that I know of with the most recent swap being about 4 months ago. I do have codes that I have pulled with a scanner, but do not remember the numbers, something related to no communication from the transmission BUS. I believe that it is a ground or a plug somewhere, but being a new member I do not have access to the files that I need to trace it. I have gone through the schematics on the main site with no avail. I am giving the symptoms with hopes that someone knows exactly what is causing this problem.Sometimes it will go through all gears fine, but it is usually only if I keep it around 1900-2000 rpms through all of the shifts. If I drive "normally" it will hold 1st gear until 2500+ rpms and the shift into second and never find third. It will run the rpms up beyond where I am comfortable and still never shift. If you let off, there is engine braking and it seems that T.C. is locked up. I can make it shift into 3rd by dropping it in neutral when it needs to shift into 3rd and it will go into 4th and the T.C. will lock up. When I stop, sometimes it will drop back into 1st, sometimes it will stay in 3rd and I have to manually shift it to 1st. I have changed the filter, fluid ( just what was lost dropping the pan ), checked / adjusted APPS voltage and most of the connections under the hood. This is a problem that started with nothing really changing on the truck. I have taken it to a transmission shop where they plugged it into a computer, hooked some pressure lines to it and tested it they stated that the transmission is mechanically sound. During my wire tracing I have found that the vacuum lines from the transmission area to the front axle were rubbed into by the front drive shaft and that there was another vacuum line on top of the transmission unhooked. This still has not solved my problem. Any suggestion would help - I will be spending the rest of the day in the shop with this truck and watching this forum.Thanks!CB

ok need some help here please ......I replaced the clutch and flywheel this past april on my beast ......put in a south bend ....and everything went great until yesterday ....now the truck acts as if the throw out bearing is not completly disengaging the clutch ...ie synchros raking ....stick hard to push into various gears especially 3 rd and reverse.....any ideas other than tearing the whole tranny back out?

This is a writeup I did on another forum last year. I've pretty much abandoned other diesel forums so I thought I would post it here. A few weeks ago my truck suddenly decided to stop shifting and got stuck in 3rd gear (limp mode). It wouldn't up-shift or down-shift. I was able to manually down shift to second but it wont shift automatically and it couldn't be manually shifted to first. I checked for codes and got a P0753 which according to the manual is: Trans 3-4 Shift Sol/Trans Relay Circuits - An open or shorted condition detected in the overdrive solenoid control circuit or Trans Relay Circuit. I started threads on two forums asking for help troubleshooting the problem. I got several responses including replacing the overdrive solenoid, the governor pressure solenoid, pressure sensor, PCM.... I really hate throwing parts at a problem so I decided to do some research and start troubleshooting. I'm definitely not an expert at automatic transmissions but I have been repairing electrical problems for 20+ years. Using the 2001 service manual and information I found through Google searches I was able to fix the problem myself. What the P0753 is basically telling you is the electrical circuit responsible for shifting the transmission into overdrive isn't working. The circuit is actually very simple. Battery power goes through a 20 amp fuse to a relay than to the overdrive solenoid in the transmission and than to the PCM. The PCM controls the overdrive solenoid by turning on and off the ground allowing current to flow. You, of course, want to check the fuse first. Than swap the transmission relay and the horn relay (they are identical) and hit your horn. If it honks, than the relay is good. The next step is to check the circuit after the relay. You just pull out the relay and insert one probe of your multimeter into the slot shown in the picture. This is the slot that sends power to the transmission. Next, you want to remove the center (white) connect on the PCM. The PCM is located on the firewall behind your air cleaner. Just push down on the tabs that are located on top of and under the connector and pull the connector out. Turn the connector over to see the pins (holes). They are marked with small number. Touch the probe to pin 21 but be careful not to jam the probe in and damage the pin. Set your multimeter to Ohms and get a reading. It should read about 31 ohms. It shouldn't read open like mine does. This tells me my overdrive solenoid circuit is open some where. It's more than likely the solenoid itself but could be the wires or the connector on the transmission. My next step is to remove the transmission pan and filter. The overdrive solenoid is located under the filter. The filter is held on with two T-25 screws. The govenor solenoid body needs to be removed first. Its held on with four 11mm bolts and two T-25 bolts. The overdrive solenoid is actually part the of the transmission control solenoid assembly which also contains the torque converter clutch solenoid. The transmission control solenoid is held on with three T-25 bolts. Also, disconnect the wire that goes to the connector. There are also two zip-ties that need to be cut off. I wanted to see exactly what was wrong with the overdrive solenoid so I removed the black plastic cover that's over the solenoid coil and the problem was obvious. The coil wire was broken. I got a new transmission control solenoid from a local parts store for $111.00. I'd hate to see what a Dodge dealer would want for it. The new one also comes with the wires. I tested the new part just to be sure. I'd hate to get it back together and find I have a bad part. The overdrive solenoid and the torque converter clutch solenoid are identical and both tested good at 31.4 ohms. I put everything back together. I used the old wiring harness because replacing it requires removing the valve body. I couldn't see doing the extra work to replace a harness that is good. The final steps included a new filter and 8 quarts of fluid. I took it out for a test drive and it works perfectly. Total cost was $153.87. Just a few additional notes on this problem: When the PCM detects a short or open circuit in the overdrive solenoid circuit it shows a P0753 code and places the transmission into "limp home mode". What that means is the PCM shuts off the transmission relay so no power goes to the transmission. This is actually what causes the transmission to stick in one gear. This caused me some headaches while troubleshooting this problem. If you look at the wiring diagram below, you'll see the transmission relay secondary circuit receives power from the PCM (through the same wire that provides power to the alternator field winding) and than the relay power returns to the PCM for a ground. When the PCM detects a P0753 it shuts off the ground for the secondary circuit. This stops the transmission relay from closing and the transmission goes into "limp home mode'. The other thing that caused me some confusion is the 2001 service manual shows pin 86 on the transmission relay as receiving power from the PCM and pin 85 being the ground back to the PCM. This is backwards from my 2000. I don't know if it's a mistake in the manual or if they switched it for 2001. Good luck with your repair. I hope this helps if you ever have a P0753. __________________