Vibration at 70 to 80

[mike101010]

I have an 04 2500 hd 6.0 135000 miles that has a vibration at highway speeds mostly 75 on the gas it vibrates if you let off it goes away until the tranny starts to slow the truck down it comes back. I've balanced the tires rotated had the drive shaft balanced no change. I replaced the granny mount and it got a little better but it's still there. Today coming home long highway run I noticed the tranny temps were almost 200 which is not normal. Could it be the torque converter causing it. Tranny been serviced was just done 10 k ago but switched to the new dextron could the high temps be from that should I go back to Dex 3

[davester]

It might be the universal joints?

[mike101010]

U joints are new

[ColoradoDave]

With regard to the vibration, take it to a reputable tire shop and tell them you are chasing a vibration issue that you think is related to the wheel balance or maybe related to a wheel with runout issues. Ask them to have the most experienced tire tech do the balance and ask if you can go in the shop with them while the tire is being balanced so you can watch. When the tech mounts the wheel on the balancer, both of you watch closely for abnormal runout while the tire is spinning. An experienced tech will be able to spot any abnormal problems. Let him balance it as he normally would and then when one wheel is complete, ask him if he will take the wheel off of the balancer completely, then put it right back on and check the balance again. he will look funny at you but insist he do it. Don't be surprised to see the just balanced wheel is now out of balance. It may take the tech two or even three tries to get the tire to balance properly when checked this way. This is particularly true if you have aftermarket rims, but it also applies to regular factory wheels too. Hunter machines do ok on smaller tires but for larger truck tires, it sometimes takes a few tries to get it right. My new to me 2010 2500HD suffered from this and this was the cure.

 

When the tech remounts the wheels on the truck, the two of you can then look for worn ball joints and if 4wd, asses the condition of the unit hubs.

 

If you still have issues after this, you've eliminated the tires and wheels as being the issue.

[Cosmic Charlie]

My 04 25 HD had the iron driveshaft that rusted and would vibrate ...