I had to go pull a guy out of the mud tonight and when I put my truck in 4wd and started to pull him out the front end started to pop really loud. I have an 06 Mega cab.. It's went away when I took it out of 4wd.. any ideas On what it could be?

 

Did you have the steering wheel turned in either direction?

 

What was your truck on, pavement? If so it is the drivetrain "winding up" and then releasing because it isn't able to slip easily.

 

I was on a paved road. He drove off in to a feild and got stuck. I was backing up strate and pulling him sideways. I just got home from the dealer and they told me I did't have enough gear oil in the front diff and that the gears are shot and that I need new ones This truck only has 6,300 miles on it and they said it was due to my wheels and lift that the 22.5"s put to much stress on the front end . So I am sure this is going to be a long battle with my local dealership.

 

I'm sure the hop was from 4WD on dry pavement.

I think the dealer is BSing you.

The front diff ring & pinion turn full-time; fill it up with fluid and don't worry about it if it doesn't make noise and still pulls your buddy's truck out of the field!

 

Lift and tires made the diff fluid low??? Hmmmm... A new one on me.

 

I will have them check my t-case Monday just to make sure it's not that.Thanks for the help. I just love how they said it was my wheels and lift

 

Big tires, 4x4, pavement, and towing will all put a lot of stress on the drivetrain, and the weakest link will see damage first. The front axle is the weakest link, but it could also be the transfer case. If I were a dealer and someone came in with damaged axles and they had big tires, I'd push back on warranty too. GM uses the same axles and I recall a comment by a GM owner that they don't honor warranty with anything but stock size tires.

 

I would like to know why you think that the front axle is the weakspot? maybe u joints, but the ring and the housing are by no means weak. also, i am not so sure about the GM comment. i have a buddy with a duramax with 8inch fabtech and 37's and the dealer did the lift and gladly will do the warranty work. He blew out is rear ring @ 2500 miles after the lift, no questions asked. this maybe just the dealer, but who knows.

 

The u joints are designed to take high sustained and impact loads. When engaged the front axle is obviously weaker than the rear axle, and the transfer case is weaker than the rear axle. The question whether the transfer case is weaker than the front axle, and which will suffer damage first. Note that damage doesn't neccessarily mean break, as scoring gears will count as damage.

http://www.thedieselpage.com/feature...-editorial.htm

What you need to know before upsizing tires on your Chevy/GMC 2500HD

Written June 2005

While some owners feel anything less than 35's are too small, the 265/75R16 has always been a popular tire size for a heavy-duty 3/4-ton pickup when considering both function and appearance. However, all of GM's 3/4-ton pickups are factory equipped with smallish 245/75R16 tires, and GM has gone so far as to deny drivetrain warranty coverage if your truck is equipped with anything other than 245's. That's just plain dumb.

Update 5/20/06: The following email message was received from a fellow member, regarding tire sizes:

"I recently replaced the OEM tires on my 2003 GMC Sierra Duramax/Allison. Costco installed Michelin X-Radial LT 265/75R16 tires. They referenced 84-03 Mast Guide as fitment approval. It appears that GM approves the 265's as an alternate for the 245's. Have you heard anything else with regard to a policy change for GM? Regards, reparkerjr"

 

Rolf at Sky's The Limit told me that the transfer case chains are usually what goes first internally.