Hellooooo all. I haven't posted very much before, so forgive me for sounding like a newb. I have an '88 Yota 4x4, 22re, blah blah blah, and I have always had a strange wheel hop that happens consistently at around 40mph. It goes away at about 45, and then it starts vibrating pretty bad between 65 and 75. It does it with both my snow tires and my summer tires (they're on different sets of rims). I've owned the truck for about 6 or 7 years, and in that time I've replaced the ball joints (upper and lower), cv shafts, front and rear bearings twice in two years (don't ask), along with every steering and suspension component on the dern thing. I've narrowed it down to something in the rear of the truck. The only thing that hasn't been replaced are the rear axle shafts themselves. Could the end of the axle where the wheel mounts be slightly off center or out of balance? If so, can you knock out the wheel studs and have the surface machined true?

 

possibly old out of balance brake drums maybe

but what's the chances of both sets of tires being out of balance?

 

Shifted Radial Belt !?

 

That's what is strange though. I just replaced the entire rear brake setup this last weekend, and as I mentioned it bounces with both my snows and radials. I hope it's not the axles, but then again it gives me an excuse to upgrade the axles and diff. Any thoughts?

 

shocks ?

 

are the leaf springs sagged onto the overloads? btw shocks won't cause wheel hop, axle wrap will though. I got a similar issue with my 87 which is sitting on it's overloads.

 

totally wore out shocks can let a small bounce turn into larger one. not a common problem but it can happen.

 

bent rim maybe

 

he already said it does it with two different tire setups that are on two different sets of rims. Doubt it.

 

possible u joint. maybe the yoke, or perhaps you have lost a drive shaft weight.

 

The leaf springs are good, shocks were done beginning of summer, and so was the driveshaft/u-joints. I actually had a worn slip & spline on my rear shaft, so I had it rebuilt. I'll pull off the wheel and brake drum this weekend and check the surface of the axle with a dial indicator. I'm thinking it might be slightly bent. It was a Dep. of Fish and Wildlife truck in it's former life, so it probably saw more than a few bumpy roads. Now that I think about it, when I did the rear brakes this last weekend, I had to readjust the e-brake, and when I spun the brake drum on the driver's side it wasn't a smooth rubbing sound. I mean the drum had more friction on a couple of spots of the drum. My old drums did the same thing. Since the passenger's side doesn't do it... hmmm... bent axle?

 

mine does the same thing. the tire shop that put the tires on didn't balance them right. so i drove to the goodyear place and they remounted and balanced them ( i've got 11.7oz on 1 of the back tires) there's a slight hump dead center in the tire. the springs are getting flater and my shocks are to short and stiff (their about 2" longer than the ones i had "

once i get around 50 it stops and still bounces slightly. check you stabilizer as well that fixed the front along with the new shocks and alignment i still need to rebuild the front end. i just added my tool box to the back of the bed and filled it with some tools to weigh it down works for now. im going to look for another tire monday