New member here. I have a 2004GMC with an LLY and a 6 speed. The tranny started to make a gear rattle around 5000 miles. I have already done the flywheel upgrade that gm offered, but that had no effect on the noise in the trans. The truck is still bone stock, and I want to start messing with it a bit, but the general keeps telling me that this noise is an inherent problem with all the 6 speeds. Anybody else have any info? I had a cummins making 400hp on the dyno before this truck, so I'm kinda missing that power. Gotta get this thing right. Thanks for your insight. Oh ya, the truck has 25000 miles on it now.

can't help on the rattle,mine had a rattle but it was the 4X4 linkage, and welcome to the site

I too had a rattle in the 4x4 linkage. I did read somewhere that ZF trannys are inherently noisy.

Welcome!! My 05 is a totally different truck then my 04 was. My 04 was loud as far as transmission and 4 wheel drive linkage. But my 05 is alot better, may have something to do with weither you had carpet or plastic floor covering.

my 4x4 linkage rattles also

Someone around here has a fix for the Tcase rattle............

Maybe the same dude that helped me decide to put a spacer at the carrier bearing in order to stop driveshaft wobble......worked great, BTW.........

I thought the only fix was to put a zip tie on it, until you use 4x4 the next time and it breaks off. At least that's what I do anyway...

Tim

Manny, that probably was me. I didn't mention the zip tie and mine has crusted up enough it doesn't do it except in rare cases. I do keep extra zip ties in the truck just in case it won't go away.

One of my little girls pony tail hair ties works well to.

I just grease mine every 10k or so and it's fine. The rattle really gets nasty in 6th gear and on the throttle.

What do you grease?