I recently had 4 new tires installed of the exact size and brand that i had before. After this was done i now have a slight vibration that can be felt in steering wheel, dash and at times cause the bed liner to vibrate that was not there before. This can only be felt when the truck in gear, foot on brake and idling. It seems to get worse after it is at full operating temp. Take your foot off the brake and allow truck to move while still idling and vibration goes away. Exhaust also seems to sound more "throaty", and tranny seems to shift differently. They did a complimentary diagnostic at the same time so i assume they hooked up an obd1 reader, could they have accidentally changed any settings in the computer that could cause this. I have been told my a friend that obd1 connections will not allow this? This truck also has a hypertech street power chip installed which has been in place for several years. This truck only has 56,000 actual miles. tia. pahoo31

 

Does it do it with the emergency brake on (foot off the brake pedal)?

Allan

 

Yes, same as if pushing on brake pedal. Since this started immediately after the new tires it seems it would be big coincident if this was somehow not related.

 

It's not the tires; they are locked in place.

I'd suspect something to do with the "diagnostic" service.

That "throaty" exhaust, worse when hot and the tranny shifting issues kind of smells like they checked your timing and forgot to hook the bypass wire backup, therefore the engine is running at base timing?

Hope you get it figured out,

Allan