Ever since i got my transmission rebuilt i get a rattle when im driving in overdrive between about 40 and 50 mph. The rpms are usually at 1200 - 1800. It sounds like its coming from the rear of the truck, Transmission, driveshaft, rearend. As soon as the truck shifts up, the sound goes away. And the only time the noise occurs, i have to be on the gas a little bit. Anyone have any ideas to what this might be? Thanks for any help

 

What type of rattle? A heavy/thick metal rattle? Or a tin sounding rattle?

 

I have the same problem jisthangin but i think its cominng from right under me and i took it to a shop and the said they could not hear it

 

The rattle actually kinda of sounds like my driveshaft might not be balanced correctly or somthing along those lines. But its only in the low rpm's of overdrive. I'm not a transmission guy, so i dont know much about them, But i thought of it even possibly being that the trans isnt balanced right, but the truck drives fine during higher speeds. I also have a wine when it goes in reverse, which i had originally before my trans blew and it started in the new trans, they replaced the valves, and now its back once again.

 

From what you describe as to when it happens with partial throttle I'm wondering if it is vibration more then a rattle. If that is the case it sounds like you are getting torque converter shudder. What causes that is not having the right fluid in it. Since your signatured doesn't tell us what year your truck is it's hard to say what fluid it needs. If it is a 2001 and newer it needs ATF+4. Many rebuilders will use either ATF+3 or some type of other fluid like Dexron 3. They then add an additive package that they claim is supposed to make the fluid comaptibile. But it doesn't work. Mopar transmission are sensitive to fluid types. If your truck is older then a 2001 then it will need ATF+3. Find out from the rebuilder what fluid they put in it. Also tell them that you think it is TC shudder. Insist they put in the right fluid. ATF+4 is a full synthetic where as ATF+3 is not. Alot of folks have had excellant results with AMSOIL Universal ATF. It is fully compatible. I use it in mine and I turned over 108,000 miles today on my 01' Ram QC 4x4. And no I don't sell Amsoil.