The forum on "DYI low speed shudder" is this what is being meant? My 06 megacab 6'' superlift, 35'' tires, does this. I just bought it Sat May 16th. I also get this wierd noise at about 50+ mph. It sounds like a bearing that is starting fail or is dry. Everything looks good on underside...

 

Does the truck have a warranty?

 

is your carrier bearing shimmed?

 

Warranty from the dealer I bought it from? Don't think so..The dealer is 3 hrs away and it didn't start doing it until the next day when i went to show it off to friends. I think the manufacture drive train warranty is 6yrs/100000mi isn't it? The carrier bearing is shimmed. There is four cadnium coated flat bar stock between the carrier bearing and the bracket that is bolted to the chassis. I assume these are the shims that came with the lift kit. But the four equal about 2 inchs..I would think if it is lifted 6'' than wouldn't there be a 6'' brop bracket. I bought the truck from a reputable dealership "AutoNow" www.liftedtrucks.com out of Phoenix, AZ..

 

Do you have lift blocks in the rear?

It could just be axle wrap that a good set of traction bars will take care of.

2" sounds about right for 6" of lift. Rule of thumb is about 1/4" of carrier bearing spacing per 1" of lift height and then adjust from there. You could try taking one plate out, or adding washers to see if you need another plate.

Tobin

 

Yeap, sounds like you have the driveshaft angles off causing the shudder.

 

Should the driveshaft have downward pressure on the carrier bearing? I noticed that the driveshaft isn't centered. The rubber bushing is squished on the bottom side...

 

Sounds like you found it. It should be centered.

 

that noise you hear at about 50... could it just be the 35's starting to howl?

 

Nitto Grappler alltrains.... a very good tire... the noise isn't a consistant howl. The noise has a off/on tune to it....I've had other lifted trucks w/35's that the tires were loud. (mud terains) This sound is different... I'm used to being around big water pumps that are driven by electric motors. It sounds like when the bearings start to fail in one of the electric motors. Kinda of like a dry bearing with a slight grind. I will be checking the driveshaft carrier bearing Sat morning....

 

drivetrain warranty is only 3/36

 

UPDATE: I removed the 3 thick shims from under the rear leaf springs and on top of the lift blocks, placed them on top so I could use all the same bolts and lower the rear a little. Then took it for a test drive. Some of the shudder I was feeling went away. So then I shimmed the driveline carrier bearing 5/8'' more than what was there due to the 6'' lift. Now there is just barely a faint of shudder. I'm gong to add another 3/16'' to 1/4'' more and that should take care of it...(for the wierd sound post)....While I had the carrier bearing loose there was no indication that the bearing was dry or bad.