Driveline Vibration at 35mph

[bluetahoe]

Looking for some input here.... I have 99 Hoe 4x4 with manual transfer case. When I get to 35 mph the truck starts to vibrate when I'm on the gas. When I let off it stops vibrating. Just for s**** and giggles I put it in 4 HI last night on the way to work and it stoped the vibration. Me and my buddy are thinking U-joints,, but I'd rather not got through the trouble of changing them if its not it.

BTW it has 113K on it and I just bought it a month ago from a dealer, so I don't know much history on it.

Thanks
Matt

 

[SNAPPY]

U-joints are not very difficult to change at all. That does not seem to be your issue though. If it was a driveline thing I would think it would do it in 2WD and 4WD. I do not know much about Tahoes as I'm a new owner myself but I would check the front and and mabe wheel balance? I know I had an issue like this on my 99 Jeep Wrangler and it was the front hub on the left side. Just a thought.....

 

[bluetahoe]

Not sure if it makes a differance but I don't feel it in the steering wheel at all. Just kinda makes the whole truck shake. That's why I was thinking ujoints. I am mechanically inclined just never experienced this issue before.

 

[41racing]

If the ujoints are factory, you can usually tell if they are, and grease is coming out of the seals I'd replace them. I haven't seen a factory joint yet that when the grease starts go seep out that is good.

 

[bluetahoe]

when i looked the other day they looked very dry

 

[fyremanpat]

Is it possible that one or more of the tires threw a weight? But under load it doesnt allow a vibration...Jus throwin it out there

 

[mygreen98]

pull off both driveshaft and visually inspect the needle bearings each cup on each ujoint. i had same issue, all looked dry, then went on to find one was so dry it had no grease in it and rusted completly.