I have a 95 T100 that shakes between 65 and 70 MPH. I have put new tires on it and the front end is new except for the idler arms. The funny thing is one day it will shake like hell and the next day going the same speed on the same road it only shakes very slightly (would not notice if I was'nt looking) Has anyone else seen this with their truck <img src="/forums/images/graemlins/confused.gif" alt="" />

I had something similar to that on a different truck. It turned out to be a ply separating inside the tire. The warmer it got, the worse it was. You may need to do some tire rotations to isolate it if that is the problem or take the tires to a shop to check balance. Mine would balance then go bad. They would rebalance them with a lot of weights in a totally different spot. They finally admitted to the defect.

Out of round tires, it happens with my dynamics thatt he PO had on there (and there like brand new so I wont bother getting rid of them) or its out of round wheels.

Have them balanced and rotated and see if at low speeds they are fine before warm up and at high speeds before they warm up. Then warm'em up and see how they do.

My truck pretty much always shakes at about 60 to 65 mph. Although it does vary depending on the road conditions and the weather (temperature outside). Its definately the tire balance, but I can't find anyone to do lug-centric balancing on my 35's

A couple of thoughts.....There is a bad set of tires being supplied from China. Dirty *&)(*& actually eliminated bonding materials between the belts and the inner rubber. So watch out for that if they are imports.. Also if it is a one time vibration, could be mud or something stuck on a rim and thrown off later. You can also find a shop that balances while on the vehicle. Big truck shops often do that.

Thanks for all the info. The reason I have new tires is because the Kellys that were on it had so many weights on 2 of the tires that they finally agreed to give me a credit towards a set of Dunlaps well the Dunlaps were pretty good but now 5000 miles later I am back to this problem. I will take it in tomorrow and have them rotated and ballanced. The last time I was in Goodyear they blamed all the problems on my "wore out truck"

I had the tires rotated and it really did not make a difference. The shaking almost feels like a wore out drive train part.

Driveshaft is tight? u-joints?

Worn control arm bushings could be a possibility... Chased my problem for quite a while before figuring that one out. Being worn will allow alignment changes to happen as the suspension cycles up & down, sometimes sticking in a shimmy - sometimes not... Definitely take a real hard look at your tires though - get them balanced well - road-force balancer if possible; if not, make the tech use stick-on weights instead of the clamp-on as you can achieve greater accuracy. Also, if you're using Toy alum wheels make sure to get them balanced using a haweka adapter... They are lug-centric wheels, not hub-centric....

Been a while...<img src="/forums/images/graemlins/cheers.gif" alt="" />

Another possibility is frame flex. I know my truck gets into an annoying vibration rhythm at certain speeds on a highway that has expansion joints, and there is a similar chassis vibration when I hit bumps/potholes at other speeds.

I used to think it was something I could tune out with better shocks, but I figured out the actual problem one time when I had the camper shell mounted a little too close to the cab- the chassis vibration made the shell contact the high-mount stop light on the cab repeatedly, in sych with the vibration. Its kind of annoying. Not sure what the best way to fix it would be...