Rough shift into 1st (48re)

[DFrank]

When I approach a stop my truck occasionally makes a loud clunk as it drops down in to 1st gear. Other times it shifts seamlessly.



I mentioned it on an earlier trip to the dealer. Surprise- he said it was normal. Any one else have these issues?



Dave

 

[Archive]

48re

48,000 miles on mine and no clunk, not normal.

 

[p-Bar]

30K no clunk, The dealer is jacking you

 

[nick05]

12k no problems and hopefully not till the major upgrades. is the transmission hot or cold when you hear this. and if your hauling something with OD off it will downshift a little harder but nothing to worry about. also just check your fluid warm to make sure its ok. (should be).



nick

 

[Rams-n-Hogs]

It's not normal. When my transmission was stock, I never even felt it shift down into first when coming to a stop. 29000 on it, (stock).



Jim

 

[RPolidora]

Well, I have exactly what you are talking about and so do many I have talked to. It doesn't do it alot but it happens sometimes when I pull in somewhere and I am in the parking lot and it just shifts to 2nd, I let off the throttle and it shifts back down quick. Sometimes I feel it and sometimes I don't. 34,000 on mine and I tow alot and it works well. I wouldn't worry about it.

 

[MCecil]

Mine does that sometimes too. Usually when coming off the freeeway hauling my 5th wl with the transmission temp over ~155, breaking early and slowly coasting to the stop sign. About 1 in 10 or 12 it will thunk going into 1st under these conditions, but the transmission has to be at towing temp. Maybe it's an '03 thing with the PCM? It's not at all repeatable so it's tough to classify this as a real issue without consistant data.

Enjoy your day and God Bless,
Merv

 

[yycguy]

My truck does this as well. So anyone found a fix yet? help, its driving me nuts!

 

[RMalone]

Mine never did the "clunk" with the stock transmission, but as soon as I got the DTT setup I get it most of the time, to varying degrees, while slowing to a stop. I have been assured it is not a problem, but it's irritating to be sure.

 

[yycguy]

Mine never did the "clunk" with the stock transmission, but as soon as I got the DTT setup I get it most of the time, to varying degrees, while slowing to a stop. I have been assured it is not a problem, but it's irritating to be sure.

So other than the annoying clunk, how do you like the DTT setup? would you do it again?

 

[boatman]

Mine has done it since day one, stock and after the DTT upgrades.

 

[JSchutz]

Mine has done it on occasion as long as I can remember. I can't reproduce it but now and then the down shift to first is very noticeable. 160k on the transmission and it runs like new so I guess I can't complain. Jeff

 

[FLynes]

12. 5K on mine and it has never made this noise. A clunk would almost make me think that you have a u-joint going bad maybe?



Frederic

 

[Alan Reagan]

Mine was doing the same thing. I took it to the dealer, they pulled the pan off and there was a piece missing out of the transmission. I believe it was part of the thrust washer components weren't installed during the original build. According to the mechanic, there was no metal in the pan but there was evidence of rubbing where the piece was missing. It would drop into first gear very hard with a clunk like you are describing. I didn't get to talk to the mechanic when I picked it up... . the service manager passed to me what he said or I could tell you exactly what it was. I know they replaced the thrust washer and associated components.



About two months later they replaced the complete drive shaft because the hard drop into first caused it to start making the "tink" noise when changing direction of rotation (reverse after going forward or vice/versa). Changing the drive shaft stopped the noise.



Since the components were installed the transmission is smooth on the downshift.



One thing, when mine was in the tow mode the downshift wasn't as hard. You may want to try that to see if that helps you narrow down the problem.

 

[lgjohnson]

Have a 2003 and the same basic truck as you..... mine does it on verrry rare occasions. On another forum I read where some of the 48RE trannies in and around that year have thrust washer lubrication issues. Usually, it won't raise its ugly head to about 50,000 miles or so... . some earlier, some later depending on use. The washer is only about a $7 part and the new part has the proper lubrication holes/ports, but it will cost a fortune to replace. My understanding is that Mopar is aware of this issue, but has elected (gambled) not to TSB or recall... . at least to my knowledge. The newer trucks have had this issue addressed in redesign. Service manager is probably aware of it and just jacking you..... nice, huh?

 

[yycguy]

12. 5K on mine and it has never made this noise. A clunk would almost make me think that you have a u-joint going bad maybe?



Frederic

Good guess, that was my 1st item I checked, but no the u-joints are just fine

 

[yycguy]

Have a 2003 and the same basic truck as you..... mine does it on verrry rare occasions. On another forum I read where some of the 48RE trannies in and around that year have thrust washer lubrication issues. Usually, it won't raise its ugly head to about 50,000 miles or so... . some earlier, some later depending on use. The washer is only about a $7 part and the new part has the proper lubrication holes/ports, but it will cost a fortune to replace. My understanding is that Mopar is aware of this issue, but has elected (gambled) not to TSB or recall... . at least to my knowledge. The newer trucks have had this issue addressed in redesign. Service manager is probably aware of it and just jacking you..... nice, huh?

I could buy that theory but there are others with newer trucks that have the same problem and they have the new version of the thrust washer? I guess its one area to look though?

 

[cerberusiam]

I have never noticed a downshift to 1st making noise even if I did it manually. There has to be something that is different between the "clunkers" and the others. Convincing the dealer of that, however, is another matter.



FYI, the thrust washer issue on the early transmissions was only really a problem when using an exhaust brake. The reverse thrust on it was causing some premature wear because it wasn't designed to handle it in that direction. There have been many axamples of trucks in that era being rode hard and put away wet and even at 100k plus miles there was no undue wear on the supposedly "problem" washer. IMO there was a whole lot of misinformation and scare stories floating around that blew the problem way out of proportion.

 

[R. Weber]

When I approach a stop my truck occasionally makes a loud clunk as it drops down in to 1st gear. Other times it shifts seamlessly.



I mentioned it on an earlier trip to the dealer. Surprise- he said it was normal. Any one else have these issues?



Dave

My 05 48RE in a 2500 is in the dealership now with same problem. They are repalcing the valve body. My 3500 is the same age and mileage (30K) but no problems with it yet.

 

[WoodChuck]

Check the TV cable adjustment. It might be a little tight. These trannys are very sensitive to proper TV adjustment. Too tight and shifts can be delayed, sensitive to downshifting and downshifting is harsh, too loose and shifts will be early and it could also slip due to reduced line pressure.