Rebelrodder

A vacuum sounds like a good plan to me. I looked for the drain and wondered how I'd get a blow gun into the top to clear it out. I figured that I would not want any stuff getting pushed back into the HVAC unit. Just to be sure I'm looking at the right part, the drain is just behind the accumulator in the fire wall. Yes? Can the accumulator be removed from it's bracket and gently slid out of the way to gain access to the drain? My hands are fairly small but I doubt I can get much down there behind it. I did get a recharge can from the parts store the other day but now we're in a cold snap so I can't test the system to see if it's working now. It's too cold outside for the PCM to turn the compressor on. I may have to wait until spring to get suitable weather again. We'll just have to see! Thanks for all of your help!

LiveOak, Mold would kinda make sense actually. I'll check to see that the pan drain is open and free flowing. If the mold is infesting the evaporator, is there a way to clean without taking the evaporator out? I gather you are saying that it is possible for R-134 to leak out slowly over time and not leak out completely. Is that right? Seems counter intuitive but I will admit to being an HVAC newb! I think I'll make sure that the cowl area is free of debris and the drain is clear then grab a can of that recharge stuff this weekend and give that a shot. Even if it only gets me through until spring that'll be better than sitting in a cold damp truck all winter! Thanks for the advise! Jerrod

Update time! I finally got a chance to get some different A/C gauges and take some pressure readings. With the compressor off I read about 30 PSI in both ports. With the compressor on I got about 65 PSI in both ports. According to the FSM that means that the system is low on refrigerant or empty. I'm leaning toward low because it can still create ice on the line going to the evaporator. That tells me there is at least some R-134 left in there. Does it make sense that the evaporator would be leaking but that the R-134 would not be all gone? That really doesn't make sense to me. The R-134 is a gas right? So a leak in the system should let all of it out until there is none left. Or am I over thinking this? Not that I've ever been accused of that! I'm only guessing that the evap. is the problem based on the smell in the cab and the lack of oily residue on any of the system connections under the hood. The FSM recommends using an electronic sniffer to verify before spending money on parts but Autozone doesn't have one for rent. Would anyone recommend going that far to absolutely verify the issue or just go with the best guess method? Also, would it be a good idea to have a mechanic recover any remaining R-134 before I start working on the system? Thanks in advance for any advice sent my way! Jerrod

I'll be getting back to work on my truck in a couple of weeks. I need to finish replacing my deck before it starts to rain again. I'd rather be a mechanic but sometimes I need to be a carpenter! I'll post back when I have more information. Thanks guys!

I appreciate your willingness but, yeah, we"re about a 12 hour drive apart. That's a long way to go! =) I agree, there's gotta be something left in the lines otherwise, how could there be any cold anywhere? I think I'll try to get a different set of gauges to see if I can get anything that way.

Hey gang! I'm having issues with the A/C system in my truck. This may take a while and make a long post but I think the context and symptoms may help the diagnosis. About a year ago when I'd turn the A/C on there would be a light smell coming out of the vents. It smelled to me like poplar leaves in the fall after they come down mostly dried up. SWMBO though it reminded her of old books bound in the 1950s and stored together in a closed room. It didn't linger long, maybe a minute or two would clear it out and all would be well. A/C performance was good at this point. I was thinking that maybe I had some poplar leaves down in the cowl that I needed to dig out. Never got to that part... I now believe that this smell is the PAG oil used to lubricate the compressor. Fast forward to a few weeks ago and we got a nice hot spell again and I hopped in the truck to go home from work and wouldn't ya know? No A/C! Drat! I've been reading a lot about A/C systems as this is the first one I've had an opportunity to work on. I'm pretty sure I have a dead evaporator and very low refrigerant level. Here's what I've seen so far: 1. A/C clutch cycles rapidly when A/C controls activated but no cold air is produced. Evidence of a bad Low Pressure Switch or low refrigerant level. 2. Tested the low pressure switch (LPS) per the procedure from the FSM. Switch checks out OK, but exhibits opposite behavior than is expected; no continuity when the compressor is on but there when compressor is off. I think this indicates that the suction side has high pressure when off but low when on, indicating a low charge of refrigerant. 3. High pressure switch checks out OK. 4. When the LPS is bypassed with a jumper wire so the compressor runs the condenser inlet gets quite warm. I don't have a way to measure how warm but it's hotter than you want to stick your finger on. At the same time the condenser outlet line is ambient temp until the rear edge of the passenger side battery. At that point it abruptly turns ice cold and begins to collect frost on the the length of the line all the way back to the firewall. Still no cold air. Seems like there may be a clog somewhere but how would that happen on a system that's never been touched? 5. I borrowed a set of gauges from Autozone. They looked brand new but I wonder if they had issues. When I connected them to the truck in the proper manner I could not get a pressure reading of any sort on the high side or the low. According to the gauges, there was no pressure at all whether the compressor was running or not. When I disconnected the hoses and broke the setup down for storage there was trapped pressure in the hoses that escaped and made me jump. Was not expecting that! LOL Clearly, there is something trapped in the lines! I cannot find any evidence of leaks under the hood based on the notion that a refrigerant leak would also carry the PAG oil with it and leave a stain on a leaking fitting or damaged line. This leads me to believe that the evaporator in the cab is the culprit. I would like to be sure before I go tearing into that particular can of worms. Is it possible to have a leak in the evaporator that releases enough R-134a out to prevent cold air making but keeps enough in the system to chill a line to ice maker level? This seems contradictory to me. Does anyone know off hand what PAG oil smells like? Buying some from the parts house just to smell it seems like a waste of money to me since I will not be performing my own recharge. That is one task I will hire out to an expert! Thanks in advance!

Hey gang! I'm having issues with the A/C system in my truck. This may take a while and make a long post but I think the context and symptoms may help the diagnosis. About a year ago when I'd turn the A/C on there would be a light smell coming out of the vents. It smelled to me like poplar leaves in the fall after they come down mostly dried up. SWMBO though it reminded her of old books bound in the 1950s and stored together in a closed room. It didn't linger long, maybe a minute or two would clear it out and all would be well. A/C performance was good at this point. I was thinking that maybe I had some poplar leaves down in the cowl that I needed to dig out. Never got to that part... I now believe that this smell is the PAG oil used to lubricate the compressor. Fast forward to a few weeks ago and we got a nice hot spell again and I hopped in the truck to go home from work and wouldn't ya know? No A/C! Drat! I've been reading a lot about A/C systems as this is the first one I've had an opportunity to work on. I'm pretty sure I have a dead evaporator and very low refrigerant level. Here's what I've seen so far: 1. A/C clutch cycles rapidly when A/C controls activated but no cold air is produced. Evidence of a bad Low Pressure Switch or low refrigerant level. 2. Tested the low pressure switch (LPS) per the procedure from the FSM. Switch checks out OK, but exhibits opposite behavior than is expected; no continuity when the compressor is on but there when compressor is off. I think this indicates that the suction side has high pressure when off but low when on, indicating a low charge of refrigerant. 3. High pressure switch checks out OK. 4. When the LPS is bypassed with a jumper wire so the compressor runs the condenser inlet gets quite warm. I don't have a way to measure how warm but it's hotter than you want to stick your finger on. At the same time the condenser outlet line is ambient temp until the rear edge of the passenger side battery. At that point it abruptly turns ice cold and begins to collect frost on the the length of the line all the way back to the firewall. Still no cold air. Seems like there may be a clog somewhere but how would that happen on a system that's never been touched? 5. I borrowed a set of gauges from Autozone. They looked brand new but I wonder if they had issues. When I connected them to the truck in the proper manner I could not get a pressure reading of any sort on the high side or the low. According to the gauges, there was no pressure at all whether the compressor was running or not. When I disconnected the hoses and broke the setup down for storage there was trapped pressure in the hoses that escaped and made me jump. Was not expecting that! LOL Clearly, there is something trapped in the lines! I cannot find any evidence of leaks under the hood based on the notion that a refrigerant leak would also carry the PAG oil with it and leave a stain on a leaking fitting or damaged line. This leads me to believe that the evaporator in the cab is the culprit. I would like to be sure before I go tearing into that particular can of worms. Is it possible to have a leak in the evaporator that releases enough R-134a out to prevent cold air making but keeps enough in the system to chill a line to ice maker level? This seems contradictory to me. Does anyone know off hand what PAG oil smells like? Buying some from the parts house just to smell it seems like a waste of money to me since I will not be performing my own recharge. That is one task I will hire out to an expert! Thanks in advance!

It sucks that you are going thru this with your truck. When I logged in today your post was at the top of the heap and scared the crap outta me. Here's why: Brutus is down!! That got may attention then made me laugh because that's what my kid's named my truck right after we got it on account of the rather less than smooth ride. When I saw the headline the first thing that flashed thru my mind was "Holy crap! My truck is dead?" Oh, wait. Whew! In any case, I'm done post whoring now. Carry on! LOL

mopartechnician, What does the Lucas Trans Fix do for the transmission? I'll be checking into the governor solenoid and pressure transducer soon. I need to swap those out in order to get rid of the dreaded 1-2 shuttle shift...

I don't claim to be an expert but as I see it you have 2 possibilities here. Either the output seal on the OD unit is leaking or the input seal on the T case is doing it. Either way, it's not too bad a fix. The T-case is kinda awkward but not super heavy. 2 dudes can pull it out and put it back in without a whole lot of fuss. The OD unit can be pulled off the trans and repaired on the bench, it's not a very large piece. You may be able to replace the seal with it still under the truck, I'm not sure. Good luck!

On the topic of caliper rebuilding, How difficult should it be to push the piston through the seal into the caliper bore? I admit that I took apart the suspect unit I returned to NAPA. Just for the fun of satisfying my scientific and mechanical curiosity. It took a lot of air pressure to pop it out. Once out I found a few bits of seal in the bore. With the seal out of the way, the piston slid through smoothly. When I tried to reassemble it that's when things went kooky. I ended up using an H frame press to get the damn thing back in there. Is this normal? If not, I think I might know why it was hanging up! Friday night special?!

Caliper maintenance in on 30 to 50 k puts me out about 4 or 5 years. Is that too long to wait? I was thinking about flushing new fluid through annually just to be safe. it's so cheap that a rebuilt caliper to replace a bad one will buy several quarts of the stuff. Oh, one last thing. I see all over that you should use brake fluid from a sealed container only. Does that mean that the cap was screwed on while it was in storage or only cans with the little foil seal stuck on top? Essentially, how sealed is sealed? Western Oregon is a wet place. I want to be sure my stored fluid is still OK to use. Thanks!

Hey all! This post my fall into the category of post whoring but I'd like to risk that in the hopes that it may help somebody else out when trying to decide what to do with their 47/48RE when it needs a bit of help. I want to be very clear here, the transmission in my truck had just a hair over 100k on it when I was contemplating this. I also know how it was driven since I know the PO of the truck. He didn't flog on it and took it in for service at the dealer every 25k just like clockwork. I felt very confident that it was in reasonably sound shape. I was experiencing TC clutch lockup slippage on the stock TC. It started when towing my 32 foot travel trailer but as the clutch started to really go south I had to pedal it even when the truck was empty. Clearly a tired clutch situation. Since this was my first auto truck and my first diesel I wanted to be absolutely sure that the transmission wasn't slipping as well. After reading a whole lot and watching a boat load of You Tube videos I figured I was in the know. I decided to call RevMax for the parts based on recommendations here and at CF. I opted to go for their Stage 3.5 TC and their towing valve body. I also added the apply lever, band strut and anchor, second gear apply piston, accumulator and the low/reverse servo. Pretty much all the standard goodies! It all went together pretty well but I must say that for my first transmission job, doing it without any gear head buddies and in my driveway was a bit of a challenge! The only thing that didn't go well was the low/reverse servo. I wound up with the version for an early 727 series transmission which is much bigger than the one in the later 727 based transmissions. I'll swap that out in the future when the trans comes out for a rebuild. At the same time I replaced the trans cooler at the front of the truck with a Derale 4 pass unit hung in place of the original one. I added a fan boosted Derale 8 pass unit under the bed just behind where I hung my AirDog. A temp gauge is my next addition but for the moment I'm trusting those coolers to keep me in the green. Just how in the green remains to be seen! The results of this far surpassed my wildest expectations! All of the parts fit well and my truck tows much better than it ever did before. The new TC locks up and holds just fine while towing though I do not have any power mods to speak of. The Hypermax programmer is very mild. I am under no delusions that the TC will hold up long term with big power under the hood but, for now it's great! Case in point, in 2012 we towed over the Oregon Coast range from Portland to Astoria for our annual camping get together with family and friends. Limping the TC clutch for most of the trip netted 9.8 mpg round trip. After the mods we took the same trip in 2013 and got 11.5 mpg with no TC clutch drama. That's a very nice increase! This trip is pretty hilly and slow so a lot of it is done in third gear. Out on the open road when I can get into OD should be a bit better. In short, a nice TC/VB combination will do wonders for your rig. IF your trans is tired and needs a rebuild, don't skip that part! Jerrod

Ah! That's the problem! I was un-checking the "Remember Me" box because I use a shared computer most of the time. I'll leave it alone and just remember to log out. Thanks so much! This site is the best!

A quick update is in order. I got to really dig into things this weekend; after bleeding the heck out of the front brake circuit I got all of the old fluid out and probably wasted a good bit of new stuff. But at least I know it's good and fresh in there! I verified that the calipers do slide easily on the guide sleeves once the pads aren't there or at least the piston is retracted to leave some space. I tracked down my problem to a suspected hanging piston in the right side caliper. NAPA swapped me for a different one and I seem to be good to go now. No more dragging brakes! Woohoo! One last question about how the brake system works. When I was checking to see if there was a hydraulic reason for the drag I never got any spurts of fluid as if there was some residual pressure at work. What I do have is a slow but steady flow from either bleeder that does not stop whether the cap is on the MC reservoir or not. Is this how it's supposed to be? I makes sense to me that it would work this way since the reservoir is above the bleed screw where the fluid comes out. Gravity/atmospheric pressure should make this happen, right? This should be the basic principal behind gravity bleeding the brakes, correct? Sorry for the newb questions. I'm still learning a lot about how brake systems are supposed to work. Thanks! Jerrod