Truck has been in the shop for about 6 weeks now. Dad and I have been working on it about 2hrs everyday. Among other things, we switched from the DMF to a Luk clutch SMF kit. I have the ZF5 in it, and a new noise popped up. It started only after the install was done. When in gear and decelerating I can hear somewhat of a grinding. It gets really noisy below 1500rpm. Dad says it's gear noise and this is a brand new noise. It never did this before. He also said there isn't any back pressure on the engine due to the straight pipe and is causing the transmission to take the load. It sounds almost like gear grinding. Like something may be rubbing the housing type of noise. It doesn't sound like a gear on gear noise, more like a gear on flat surface noise. It also happens a little when accelerating. I'm stuck. I've been reading on the general idea of what the noise could be and it could be a million things. I was wondering if you guys had any input. I WAS NOT THERE WHEN HIM AND A WORKER PUT THE TRANS BACK IN. Was also told to possibly check trans fluid level, which not exactly sure how to do. Thanks!

 

Yiur are describing gear rollover. Perfectly normal when upgrading to SMF

 

What's the best way to render it? Or is it ok? I am reading that I could go to a 50wt ATF for the trans to help it? If so, I'm doing it first thing tomorrow. I dislike thay sound, it will drive me nuts because it sounds like it's destroying the transmission, even though I'm guessing it isn't??

 

It won't hurt anything. Only run the fluid recommend for that trans. Over filling it 1qt will help with the noise. After a week of driving it you won't notice it anymore.

 

There are two ways to remove the noise.

1. Install a dual mass flywheel. That's why the truck had a dual mass flywheel from the factory.

2. Turn the radio WAY up.

It's not going to hurt the transmission.

 

I like your radio idea :P

 

Definitely sounds like gear rollover to me. I noticed the same thing when I switched from the factory DMF and clutch to the Luk SMF and clutch. As others have said, you'll get used to it, and I've gone over 80K with my setup and no trans issues to date.

I don't like the noise much either, so I modified my driving habits and keep the RPMs up higher than I did with the DMF. Now the only time I hear it is if I lug it off the line with the trailer hooked up or am driving really slow through a campground or parking lot in 2nd. Usually shifting to 1st alleviates it. You'll get some odd looks from onlookers when they hear the noise, as they are likely expecting the drivetrain to drop out right then and there.