I have a 2003 3500 SRW HO with the 48RE tranny. It now has 14K miles on it. Last week when I has on it about half throttle just after it had locked up in 4th, I had to let off suddenly. A horrible sort of grinding noise came from the tranny three times qiuckly. After that I tried letting off suddenly while it was locked in 4th at higher speeds as well and I always get 1 to 3 grinding noises from the tranny Does anybody have any idea what this may be? I have not had time to take it to the dealer yet and thought I would try and educate myself on the problem before I go.
Thanks in advance.

 

Are you sure it's the tranny? Sometimes if I let off real quick on mine I will get a barking sound out of the turbo, sounds kinda like what you describe. There's a few threads on it if you search on turbo bark.

 

How is it shifting?
Soounds like turbo bark to me also.

 

I third the turbo bark...I have a hard time avoiding it in the same situation when shifting into OD. I think my truck wants to get there too quick with the power mods under light throttle...

 

I don't think it is turbo bark as I barked the turbo more than a few times on my last trucks. This seems to be a much lower tone than the turbo bark I have heard and the whole truck shudders. Usually in 3 distinct pulsation waves, not just one squeak like I have heard from my other turbos. This is my first auto though as my last 2 rams were sticks. I did recently pull a heavy load with it and it seems to shift poorly into 4th since then..... and all of a sudden this noise?

 

I was going to send this yesterday , But got a call, not hearing the noise - but possibly the converter going south for the winter early

 

I'm able to get it almost any time I pull the trailer and let it shift into OD by itself. Therefore I don't do it that way often. Definate chatter/grind noise. It's too much of a stretch (ration) for the transmission to shift with it under load. Need to let up on it. Other option is to stand on the throttle until it gets above it's sweet spot.....then let up on the throttle and it will drop in smoothly and you can continue on. I contribute it to poor transmission design. Thought we all knew that. ;-)

 

I've said it before so I'm not trying to be obnoxious. Check to make sure your tranny dipstick tube isn't vibrating against the a/c line it runs next to. The motor leans that way under load and the TC lockup in O/D is a pretty good load if you're in the throttle. It can eventually wear through the a/c line if it is. You'll see the mark where they cross if it's too close and rubbing at TC lockup. That's what it was on mine. I moved the dipstick tube over a little. Haven't had the noise since.