Chevy G20 Cargo Van 1992 - High Speed Problems

Hello All!

Chevy G20 Cargo Van 1992

I've been using my van daily for the past 10 years. For as far as I can remember, while traveling at a STEADY speed of anywhere between 30 - 40mph, the van starts viberating somthing like if you are on a Coney Island roller coaster. If I accelerate to go faster or if I deccelerate to go slower, the vibration disappears. This happens when the engine is under pressure or going uphill. I think the vibration is more concentrated from the rear of the van.

Any ideas would be great! Thanks!

tires

EGR valve. Replace it. costs like $30-40... 10 min job...
Make sure you test the one you have first, as it may not be your egr valve that's causing this...

Could be tires out of balance ... (you could have lost a weight shortly after initial balance). My 67 Ford Mustang did that at 60 mph them smoothed out again at 70 mph. Balancing the old tires didn't seem to help. Once the tires wear slightly out of round may as well toss them. New tires fixed all my problems.

Jay

My G30 has done this since I have owned it, and balancing 4 new tires didn't change anything. But the second time I had to replace the differential yoke seal I got the idea that the driveline might be out of balance. I will get it rebalanced as soon as I fix the four other problems that are ahead in line...