48RE transmission issue

[MSkyrman]

My truck with the original 48RE transmission now has 117,000 miles. I have the Edge Juice with Attitude and never run more than the 'tow' setting. For the past 4 years we have been fulltime RVing, so a fair amount of towing our heavy fifth wheel across the country back and forth. I have never had any service issues with the transmission...standard fluid and filter replacement, no adjustments to the bands to my knowledge. The last time I had the trans fluid replaced they did note it smelled a bit burnt and recommended a different transmission fluid which doesn't break down and burn at higher transmission temperatures.

The issue I'm experiencing is this. After I put the truck in reverse, then go to drive, it acts like its stuck in first gear and revs real high before shifting to second gear. By accident I discovered if I shifted from reverse into park, then to drive, everything worked normally. What gives? Is this a sign I need to have some adjustments made?

[cerberusiam]

If you haven't done it yet replace the gov pressure solenoid and transducer before trouble shooting more. It could be a VB linkage issue or valving issue or the above sensors.If your fluid has had a burnt smell you might have somethig stuck in the solenoid that is causing the issue or the fluid change knocked it loose.

[JLandry]

You should definitely have the bands adjusted next time you drop the pan for any reason. One band adjuster is inside the transmission and the other is on the outside. They're supposed to be adjusted every 30,000 miles when towing.

But your problem sounds like it could be the gearshift linkage is either loose or misadjusted. I believe there's a bushing in the linkage leading down to the transmission which can pop out or fail. Since this doesn't require dropping the pan, you might try it first.

Good luck,

John L.

[WoodChuck]

Originally Posted by MSkyrman

The last time I had the trans fluid replaced they did note it smelled a bit burnt and recommended a different transmission fluid which doesn't break down and burn at higher transmission temperatures.

Did you take their recommendation and put something other than ATF+4 in it? If you did that could be the cause of your new problems and I would recommend a complete flush. Also make sure the filter gets changed. BTW the ATF+4 is a synthetic long life fluid already.

The first time I changed my ATF it smelled burnt and looked discolored too and I was concerned, I later found out in the factory service manual this is normal and to be expected for ATF+4 and is not an indicator of any problems with the fluid.

As far as the bands go the most important one is the front band which is accessible form the outside, (it is a shifting band). The rear band isn't as important as is doesn't do any shifting, it only holds in reverse and manual low.

If your truck is an 03 or 04 you should probably have the TV (throttle valve) cable looked at and adjusted if needed.

[cerberusiam]

Originally Posted by WoodChuck

The first time I changed my ATF it smelled burnt and looked discolored too and I was concerned, I later found out in the factory service manual this is normal and to be expected for ATF+4 and is not an indicator of any problems with the fluid.

I am going to disagree with that due to personal experience. I ran 40k and toasted the direct clutches with too much power, I mean REALLY toasted them to the point it ruind the input shaft. Slipped the TC clutch several times too many also and never had a burned smell, fluid never even lost the red tint. The only indication was excessive clutch material in the pan and fluid.

If ATF+4 is smelling burned and showing dark it got HOT too many times for some reason. It just doesn't do show that under normal use. Something is not holding the weight or power. If the trans is stock its probably multiple places slipping.

I will agree recommending something other than ATF+4 for heat is ridiculous. It handles heat better than just about anything out there aside from some tractor fluids.

As far as adjusting the band, the symptoms do not indicate that is needed. If there is flair shifting, loss of second gear, shuttle shifting, then maybe that would be an option but a band adjustment does NOT CURE ALL THE PROBLEMS. In addition, thats a really good way to make sure you need a rebuild sooner rather than later if is not done correctly, and, you cannot correctly adjust the flex bands for wear on the outside adjuster.

These bands are made for a one time adjustment and thats it. If it needs to be tightened down then there are other issues like the band stretching or excessive slipping that will not be fixed by an adjustment. This is not true if the OEM has been replaced with a rigid band.

[JLandry]

Originally Posted by cerberusiam

These bands are made for a one time adjustment and thats it.

The service manual clearly indicates regular band adjustments... every 30,000 miles for "most vehicles."

Besides shifting problems, failure to regularily adjust the front (kickdown) band can cause it to become loose enough so that the link strut can fall out... just ask TDR member Dodoro: Front band wedge fell out -Reason for no 1 -2 shift

Best regards,

John L.

[WoodChuck]

Originally Posted by cerberusiam

I am going to disagree with that due to personal experience. I ran 40k and toasted the direct clutches with too much power, I mean REALLY toasted them to the point it ruind the input shaft. Slipped the TC clutch several times too many also and never had a burned smell, fluid never even lost the red tint. The only indication was excessive clutch material in the pan and fluid.

If ATF+4 is smelling burned and showing dark it got HOT too many times for some reason. It just doesn't do show that under normal use. Something is not holding the weight or power. If the trans is stock its probably multiple places slipping.

I will agree recommending something other than ATF+4 for heat is ridiculous. It handles heat better than just about anything out there aside from some tractor fluids.

As far as adjusting the band, the symptoms do not indicate that is needed. If there is flair shifting, loss of second gear, shuttle shifting, then maybe that would be an option but a band adjustment does NOT CURE ALL THE PROBLEMS. In addition, thats a really good way to make sure you need a rebuild sooner rather than later if is not done correctly, and, you cannot correctly adjust the flex bands for wear on the outside adjuster.

These bands are made for a one time adjustment and thats it. If it needs to be tightened down then there are other issues like the band stretching or excessive slipping that will not be fixed by an adjustment. This is not true if the OEM has been replaced with a rigid band.

You can disagree all you want, I am quoting from the factory service manual and from what you're saying about the bands you're not qualified as a transmission expert.

I agree that his symptoms don't indicate a band adjustment problem but the OP stated he didn't know if it was ever done which is why I recommended it. A front band adjustment is very easy to do and should be done every 30k miles. All bands and clutches wear from normal use just like your brakes. You've got to be kidding if you think a rigid band can wear but a flex band wont.

[cerberusiam]

Originally Posted by JLandry

The service manual clearly indicates regular band adjustments... every 30,000 miles for "most vehicles."

Besides shifting problems, failure to regularily adjust the front (kickdown) band can cause it to become loose enough so that the link strut can fall out... just ask TDR member Dodoro: Front band wedge fell out -Reason for no 1 -2 shift

I am well aware of the service manuals recomendations. I am also aware of who wrote that manual and the real world implications of following it. There is such a thing as "planned obsolesence" and looking at the factory band and the service manual it just kinda jumps out at one.

As for the band strut falling out, that was due to a misadjustment to start with, or the lock nut coming loose, or a failure in the band apply linkage. If all the pieces are in good shape, set correctly form the start, and locked correctly you can burn the band material off down to metal and the strut will still not fall out. There is not enough band material to allow that.

On my 05 I validated the band adjustment at 10k. It was almost perfect and still had plent of threads showing. I ran to 105k towing 10-15k frequently with power level up to 450 hp. I burned upo the direct clutch pack and when we tore it down the front band was perfect and well within the intital setting specs. Set it once every 100k and if everything else works correctly it doesn't need frequent adjustment. If it does it is a symptom of another problem.

Here is what the OEM band looks like. It has very little material to scrub off. If you have to adjust frequently it will be down to metal and eating the drum. I am not advocating never adjusting, just not using it as a cure for ANOTHER problem that will eventually trash the trans.

[cerberusiam]

Originally Posted by WoodChuck

You can disagree all you want, I am quoting from the factory service manual and from what you're saying about the bands you're not qualified as a transmission expert.

Never portrayed myself as an expert, and , yes I can disagree with the service manual in lots of instances. Particularly because I have burned up and spun the lining off enough bands to know what is going on with them. I have burned up enough clutch packs and had to track down the source to know a few things from a practical application stand point that is in direct conflict with said service manual. Its a "been there, done that" attitude.

Good bands and clutches are 200-300k, or more, wear item depending on use. Even cheaper ones like OEM are NOT a 30k wear item if things function correctly. If you want to believe that all I can say is the automotive repair industry needs your support. Talk to some high performance builders about where the issues are and the impact on wear patterns and how they are solved for high HP applications. It will give you a whole new perspective on the stock system and some of the service manual reccomendations.

Sit down with OEM flex band and an aftermarket rigid then tell me which one will take frequent adjustments and which one should not ever be touched after an intitial set. See my previous post for the why and quantifiable experiences.

[MSkyrman]

Originally Posted by WoodChuck

Did you take their recommendation and put something other than ATF+4 in it? If you did that could be the cause of your new problems and I would recommend a complete flush. Also make sure the filter gets changed. BTW the ATF+4 is a synthetic long life fluid already.

The first time I changed my ATF it smelled burnt and looked discolored too and I was concerned, I later found out in the factory service manual this is normal and to be expected for ATF+4 and is not an indicator of any problems with the fluid.

As far as the bands go the most important one is the front band which is accessible form the outside, (it is a shifting band). The rear band isn't as important as is doesn't do any shifting, it only holds in reverse and manual low.

If your truck is an 03 or 04 you should probably have the TV (throttle valve) cable looked at and adjusted if needed.

I'm pretty sure it was Schaeffers All Trans Supreme, 204, something like that. The problem I am having did not coincide with this change in transmission fluid. I started having the problem before that by about 10,000 miles or so.

Should I take this to a transmission shop, or just a good diesel shop, to have it checked out?

[JLandry]

Originally Posted by MSkyrman

Should I take this to a transmission shop, or just a good diesel shop, to have it checked out?

Either one as long as they're experienced with Dodge diesel trucks and transmissions... be sure and ask.

Good luck,

John L.

[WoodChuck]

Then you should do the governor pressure solenoid and transducer like Cerberusiam suggested or do that plus a recalibrated valve body from somebody like Suncoast or a shift kit with a through cleaning of the VB.

[MSkyrman]

Originally Posted by WoodChuck

Then you should do the governor pressure solenoid and transducer like Cerberusiam suggested or do that plus a recalibrated valve body from somebody like Suncoast or a shift kit with a through cleaning of the VB.

I am now getting a MIL with code P1740-Rationality Error detected in Tcc solenoid or OD solenoid...does this additional info change anything in your recommendations? No other symptoms with the tranny...just towed 1,500 miles from Mass to Florida. Is this repair work you mention above constitute a tranny "rebuild", or is that something more involved and more $$$?

[WoodChuck]

I don't think either one of those items would cause the condition you explained in your original post (hanging in first gear). To answer your question, no changing a valve body or a shift kit is not anywhere close to rebuiding a trans, valve body work can be done with the tranny still in place.

[cerberusiam]

Originally Posted by MSkyrman

I am now getting a MIL with code P1740-Rationality Error detected in Tcc solenoid or OD solenoid...does this additional info change anything in your recommendations? No other symptoms with the tranny...just towed 1,500 miles from Mass to Florida. Is this repair work you mention above constitute a tranny "rebuild", or is that something more involved and more $$$?

It depends on what is causing the issue. Now the other 2 solenoids are showing issues that indicate they are not reacting like they should.

Your original problem has been cured by changing the gov solenoid. If you have not done that yet, its the first step. The P1740 could be the solenoids getting dirty, the wrong fluid, or possibly the TC going bad.

If you have been doing a lot of towing over the life of the trans it may be time to pull it apart and check things out. The diretc clutches and TC clutch are the weak points and once they start going its time to rebuild.

FYI, do NOT order just a VB. Find a competent builder and have your done. With too many of the VB swaps you are getting a modified 47RE VB because there are so many more of them available. While they work there are subtle nuances that throw gremlins into a 48RE system that make it har dif not impossible to resolve issues.