Shakes at 60 mph and above

[facedaday]

Hey, I've got a '71 K-5(4" tuff country lift, 35" bfg muds). The truck does pretty well on the highway until I get at around 60mph and it shakes from then on. I just got an alignment a few weeks ago and the tires were balanced last summer. Anyone have any ideas on what I can do to fix the problem?

 

[bigredblzr]

Do you have a slip-yoke or a fixed yoke T-case? Did the vibrations become an issue immediately after putting on the lift? Have you shimmed your axle yet?

 

[mudjunkie 82]

CK-5 /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif

 

[Blue85]

If it has done this ever since the lift, chance are your U-joint angles are wrong. Do a search on this.

Otherwise, check both U-joints for wear and lube.

 

[facedaday]

I don't know whether it is a slip yoke or a fixed yoke...I do know it's a 205 transfer case. And it did shake somewhat before I got the lift kit...it just seems like it's worse now...or maybe just more annoying /forums/images/graemlins/mad.gif I had the local off-road shop put the lift on for me. I dont believe anything is shimmed. I've taken a good look at it and havent seen anything like that under there. Thanks for the replys.

 

[bigredblzr]

NP205 is a fixed yoke I believe. So it is probably just that you need shims; no biggee. They go right in between the spring perches and the bottom of the leaf pack. On a 4" lift, I'd say some 4-6 degree shims should do the trick, but I'm not certain. I have 8 degree shims on my truck and I have 5 1/2". Like Blue85 said do a search for shims or u-joint and you'll find something...

 

[SCJimmy]

I think he's referring to an actual shaking of the truck, not a driveline vibe. If it's wheel/tire related, try swapping the wheels front to back. you could also have a tire that is not seated on the rim properly.

[ QUOTE ]
(From Centramatic's web site FAQ's)


What about mis-mounted tires or improperly seated beads?

This problem can be found by inspecting the area where the wheel and tire meet. A guide rib or circumference ring is molded into the sidewall of the tire. Measure the distance from the wheel to the guide rib (approx. ½ inch depending on tire brand), at the top, bottom and both sides, a variance in this distance indicates a mis-mount. A mis-mounted tire will roll out of round. This leads to erratic tire wear and vibration, regardless of how well it is balanced. Reseating the bead properly corrects the problem.




[/ QUOTE ]

I had a similar problem. Turmed out to be crappy wheels. I am running Centramatic balancers on my 8 lugs with 35's, and they are smooth at highway speeds. A little $$$ solution though.

Just my .02
Byron