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kedlin88

AC noise/torque lock up issue problems

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Ok, first off I bought this truck about 1.5 months ago and before I bought it, it had two brand new batteries and a brand new alternator installed. To be honest when I test drove it I don't believe the TC ever locked up(didn't know what TC lockup was when I bought it.) The transmission fluid was real brown and smelt really burnt, so I dropped the pan and changed the fluid and filter and adjusted bands(about 6 qts is all i got changed out. I didn't do I complete flush.) So now when the truck is cold, the TC will lock up at about 45-55mph, and the transmission starts to shudder until I get up to speed. After I get on the hwy it will stay locked in for about 4-5 miles then it starts to unlock and lock a couple of times till it finally stays unlocked and wont relock the rest of the drive into work. So I think I am starting to have the a/c noise issues. I first checked the codes and I get no codes. When I got home I checked the DC voltage at the battery and get 14.3 or so. I then switched my meter to ACVs and it reads 30.8???? I believe I have the meter set right for AC but not sure. I included a picture with the setting to make sure its right. I then remove the alternator fuse and check again on ACVs and it drops down to 26.3?? Are these readings right? When I check the ACVs at the fuse I get nothing, I just get the readings at the battery??

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I'm not sure if my volt meter is on a low enough setting for the ACVs. I also don't know if the fluid change had something to do with it? Fluid is burnt and brown in color. Then I replace 6 qts of new fluid and it starts this? Maybe it needs a complete flush?

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Im not sure if this had anything to do with my bad gas mileage also. I got 12.5 mpg when I bought the truck completely stock. Then I added 4" straight pipe and a BHAF and I have ran two tanks and it only brought it up to 13mpg.

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Alrighty, I removed the alt fuse again and took for a test drive. And still the same, not locking up on the hwy. Also, when I removed the alt fuse, my airdog 150 ran all the time??

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Tranny shudder is almost certainly a sign of a slipping torque convertor, and the fact that your fluid was burnt smelling re enforces that. What type of fluid did you use? I dont think I would be getting too carried away with anything else until you can get a professional opinion on the health of your transmission.

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Tranny shudder is almost certainly a sign of a slipping torque convertor, and the fact that your fluid was burnt smelling re enforces that. What type of fluid did you use? I dont think I would be getting too carried away with anything else until you can get a professional opinion on the health of your transmission.

Valvoline ATF-4. This is kinda what I'm leaning towards. With only dropping the pan and not doing a full flush there is still a higher ratio of old fluid vs new fluid?? Thanks,

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I was able to get 10-11 quarts when I serviced mine over the summer so yes there is still quite a bit of old fluid in the system in your case. I removed the cold side trans cooler line from the cooler, placed it in a bucket and had someone start the truck in neutral. The fluid now is coming out of the line into the bucket at a good rate, the second you see the flow interrupt it is time to shut the truck down to avoid cavitating the pump. Then it's time to drop and clean the pan, I removed the hot side trans cooler line and drained everything out of the cooler and the lines. Also if you still have the factory check valves in the transmission heat exchanger (follow the trans lines up to the passenger side of the block) there is likely some fluid left in there as well. I removed my checks long ago, so everything was able to drain back out. I left mine drip overnight and gained another quart or two by doing that. It is a little time consuming, but in the end I was able to evacuate most all of the fluid, which is the whole point in the first place....With that being said I don't know that doing this would help you in any way, if the torque convertor is in deed toast. Any good transmission shops in your area? It cant hurt to just drop by and talk to someone and pick their brain, shouldnt cost you anything unless you agree to let them do a formal diagnosis.

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It sounds like the line pressure is low, could be due to bad fluid and/or internal seals and o-rings leaking. As the fluid heats up it thins out and goes around the worn seals and o-rings. I've fixed several cars and my own shop van by just taking the pan off, adjusting the bands, changing the filter, and refilling with Lucas and trans fluid. My shop van would shutter at freeway speed going up hills after driving for 50mi, the t/c clutch was slipping, that when it had 235k. It now has 285k. I wouldn't do a complete flush on it. I've had several cars towed in with bad trannies after a complete flush at a "lube and tune" shop.Why this happened I'm not sure but trans fluid is very high in detergent.

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I have done some reading after I posted this and seeing a lot of people are getting 30ACVs with a cheap volt meter, (which is what mine is) I do not have access to a good one or a fluke. I am defiantly leaning towards a TC issue and not electrical. I am going to drain tranny fluid again and take off the lines to get more out and see what happens. Can I remove the valve body and give it a good cleaning? What should I be looking for? Is there any way to perform a pressure test? Can I up the pressure by an adjustment screw? Thanks guys

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Anything above 14 VAC is a Digital Volt Meter issue. That is most likely designed only for 60 Hz household power and thats all. A high quality Fluke or SnapOn will read multi-frequencies that vary.

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I heard that its better to change the trans fluid gradually or about 6 qts at a time like your doing.I'm no expert but just some thoughts;Check for ground resistance between the Alt housing and the engine block. If need be run another ground off the alt housing to the batter negative sideAnother is the trans speed sensor ?Another is running a torque converter lock up switch to see what happens. I know there are write ups on this and you have to remember to unlock it when it's shifting and or stopped. Something like that.Another is to have very clean battery connections.I had to find a Fluke Meter off Craiglist because mine was the lesser expensive one and wouldn't read right like yours does.

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It seems to be the opinion that performing an actual flush nets bad results although I have never personally experienced any. Just performed the 60k mile service interval on our Mountaineer. I did everything except the trans service which required a "fluid evacuation" as they call it on the sealed units these days. I looked into doing it myself but it is nearly impossible without the proper tools. We have experienced no issues with it, shifts just as smooth and crisp as before the service. I think they are not as bad as they are made out to be as long as proper service intervals are followed from day one. I believe it is more likely to be the vehicle that has been severely neglected that gets a flush for whatever reason and then experiences problems....I am no expert this is just my take on the matter. The procedure I listed above is by no means a flush, it is just a thorough replacement of fluid and will not cause any issues. If you were to just drop the pan and replace the fluid you lost, you would have to increase your service intervals by 50% or more to keep up with OEM recomendations.How many miles on this transmission? I don't know of any ways to visually inspect a valve body, usually the damage occurs from within. If the trans has a bunch of miles on it or was abused, it may be time for a new TC and valvebody. This is where finding a competent diesel trans builder that is not out to clean your wallet out is worth his weight in gold.

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It seems to be the opinion that performing an actual flush nets bad results although I have never personally experienced any. I think they are not as bad as they are made out to be as long as proper service intervals are followed from day one. I believe it is more likely to be the vehicle that has been severely neglected that gets a flush for whatever reason and then experiences problems....I am no expert this is just my take on the matter. The procedure I listed above is by no means a flush, it is just a thorough replacement of fluid and will not cause any issues. If you were to just drop the pan and replace the fluid you lost, you would have to increase your service intervals by 50% or more to keep up with OEM recomendations. How many miles on this transmission? I don't know of any ways to visually inspect a valve body, usually the damage occurs from within. If the trans has a bunch of miles on it or was abused, it may be time for a new TC and valvebody. This is where finding a competent diesel trans builder that is not out to clean your wallet out is worth his weight in gold.

I keep hearing the same thing. "I flushed my tranny, now its broke??". Personally I don't see how that could happen. I am going to do the procedure you listed above and see what happens. The truck has 266,700 miles on it. It had two owners before me, The guy I bought it from said he never touched it. SO, there is a possibility that it is the original tranny. It wont be till thanksgiving break that I get a chance to change the fluid, so ill update on what happens then. Also, just as a side question as posted above, when I removed the 140amp alternator fuse to see if that changed anything, my airdog 150 was running all the time?? We I installed the fuse back, the pump went to normal(primed after key was turned over, then shut off) Is this just how its wired up?

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I keep hearing the same thing. "I flushed my tranny, now its broke??". Personally I don't see how that could happen.

The old fluid is what holds the worn transmission parts together. The fluid and those parts wear together. When you replace it with new fluid, it starts breaking down those worn out parts and things fail. Once the fluid gets burnt or is old and well used, the damage has already been done to the clutch packs and the TC and valve body. You put new fluid to it and the fresh detergents "clean" everything. Starts taking things with it and causes the the failures.

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Diesel4life is right. All the transmissions I see go bad after a flush have been neglected, never serviced. If you service it on a regular time/mileage interval you should see a long and trouble free life from it. The newer transmissions that service don't have a pan, just a cover over the electric shift solenoids and a drain plug on the trans' case. I wouldn't remove the valve body unless you were going to replace it. To check the line pressure you need an oil/transmission pressure 300psi gauge with a 6' or longer hose and the proper fitting for the trans, this is best left to do at a repair shop. There are 5 different ports to test at and it is a long procedure.

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Like on the little 1996 Dodge Ram 1500 with a 46RE I've serviced the trans every 30k miles or every 3rd year. (Mostly every 3rd year). Magnet is clean every time I drop the pan, the fluid is bright red, no debris in the pan either. No need for a flush because the truck was never abused. I do tow with it but I don't get crazy about it. Yeah I know the book says it will haul 8k pounds but even then I tend to lock out over drive and slow down while climbing grade to keep from over heating the trans. Yeah yeah I know I need to install a trans temp gauge on this beast.

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An APPS or TPS problem would cause a fluctuation in RPMs and generally does not affect transmission functions. The shudder you mentioned in your first post is hard to be duplicated by anything else other than a TC. Not to say it cant be something else. Like mentioned earlier a competent trans shop would probably be your best bet at least for diagnosing, then you can decide what you want to do from there.

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I got a Borg Warner HD solenoid and new transducer order. I also was able to get my hands on a better volt meter. Battery is reading 0.3 ACVs, and drops down to 0.02 when the grid heaters kick on?? Looks like a new alt. for me. Has anyone had good luck with a specific alternator?? I would like to pick one up at a local parts store, so I can get it in tomorrow. I have a oriellys, autozone, napa, carquest, and advanced all near me, but if I can get a better one off the internet I would order one. Thanks,

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I can say many times..... always buy a new Alt. Never get one rebuilt as they don't really do a thorough job anymore. I think the Nippon Denso alternator is a better alt. than the Bosch. Those are the only two choices for our trucks. If you already have the Bosch you will need to change the wire connectors a little to adapt to the Nippon Denso. I did this and think it's worth it.One of the best prices for a new ND alternator is to order one from Larry B's. Just google it and he will come up and you will see one of the best prices. All he sells is parts for our Ram trucks.Another thing about the ND alternator is Larry B's sells a new diode bridge only for that alternator if you ever burn any diode.As far as going to transmission shops..... I don't trust many of them unless they are well recommended. I have been smoozed many times by transmission shops that act like they know everything, when in reality all they really do is buy transmissions from someone else that knows how to rebuild them. Many only know about changing yours over to a rebuilt trans bought from somewhere else. Be careful... many are good talkers know how to say the right things.

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I can say many times..... always buy a new Alt. Never get one rebuilt as they don't really do a thorough job anymore. I think the Nippon Denso alternator is a better alt. than the Bosch. Those are the only two choices for our trucks. If you already have the Bosch you will need to change the wire connectors a little to adapt to the Nippon Denso. I did this and think it's worth it. One of the best prices for a new ND alternator is to order one from Larry B's. Just google it and he will come up and you will see one of the best prices. All he sells is parts for our Ram trucks. Another thing about the ND alternator is Larry B's sells a new diode bridge only for that alternator if you ever burn any diode. As far as going to transmission shops..... I don't trust many of them unless they are well recommended. I have been smoozed many times by transmission shops that act like they know everything, when in reality all they really do is buy transmissions from someone else that knows how to rebuild them. Many only know about changing yours over to a rebuilt trans bought from somewhere else. Be careful... many are good talkers know how to say the right things.

Ok, so I went to NAPA auto parts where they said they had a BRAND NEW alternator, I had them test it while I was there and hooked my meter to it and it was putting out 0.7 ACVs. Could this be with it being brand new. I also just looked at the LarryB alternator, Its only a 120 amp alternator. I believe stock was 136 amp. Only extra thing I have on my truck is a set a gauges. Will this be enough amps? THanks

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Its only a 120 amp alternator. I believe stock was 136 amp. Only extra thing I have on my truck is a set a gauges. Will this be enough amps? THanks

lol The only time you would see the need for that many amps is if you are idling with everything on the pickup turned on high and a trailer with a ton of marker lights on it all on and jumper cables hooked to something else. with your PIAA halogen lights burning bright ect. Just throwing a theoretical example out there. Or if you turned everything on and on high while the grid heaters are still cycling.

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Kidlin88 is right about tranny shops. Find a highly recommended 1 owner shop that's clean. I've had to deal with tranny shops because I haven't done major trans repair for 20 years. I sublet or recommend a shop. I all ways ask for feed back on the repair. I've changed shops a couple of times over the yers because of bad feed back or the owner feeding me a lot of bull. Some shops have called to offer a referral fee if I send customers their way. Those guys you stay away from.

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Failed diodes. I've seen them fail out of the box. Most re-builders or manufactures tend to cut corners and use cheaper China/Japan diodes instead of quality American so the AC voltage is higher.

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Failed diodes. I've seen them fail out of the box. Most re-builders or manufactures tend to cut corners and use cheaper China/Japan diodes instead of quality American so the AC voltage is higher.

Do you guys know If the LarryB Alternator is tested for ACVs before its sent out the door? I would hate to get a new one from him like NAPA and have it fail out the door. THanks,

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I recently did a new alternator due to occasional VAC spike and got a new DENSO from O'reilly's. It said it was made in USA. So consider that for the future...

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I recently did a new alternator due to occasional VAC spike and got a new DENSO from O'reilly's. It said it was made in USA. So consider that for the future...

See I called my local O'reilly's, and all they carried was reman DENSO. They did not even offer or list a NEW one.

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