My truck is riding like I'm on rumble strips. It smooths out at cruising speed and when I let off the gas.
I checked the drive shaft for missing weights
but I don't know what else to look for

any ideas?

I guess I'm going to go to a shop this afternoon unless I can figure this out.

oh yeah, 93 4runner 3.0 auto 311189 miles

thanks

 

Also, tires are BFG all terrain at 49.5 psi and on my last 100 miles I got 22.9 mpg

 

It sounds like your driveshaft's u-joints are worn out.

 

X2 drive shaft u-joints. I had the same thing happening. The joints felt tight to the hand when checked even with it on the rack to have them removed. When the shaft was pulled they showed that most of the bearing pins were missing. They nearly fell apart once the shaft was removed.

 

Why are you using such high pressure in your tires? Try lowering the pressure to like 32 psi and see what happens.

 

I was riding the highway and the tires say to inflate up to 50 psi

 

Are they wearing evenly? I would think the center of your tire would be wearing out a lot faster than the sides. Most of the time the max PSI is for when you are carrying loads.

I would have to agree with the u-joints though. Sounds exactly like what my 1990 did. Especially since you have 300K + on that thing. That's cool. They only cost about $6 at the parts store, might as well replace both while you're in there.

 

I always went by the rule "Up To" meant max pressure if you were hauling a load.. If your not hauling heavy loads , 32 - 35 pounds of air is plenty.. That will make it ride rough and wear the center of the tire.......

 

You beat me to it, lol

 

how much is "heavy" for this thing? I had a large pile of wood, way too much gear and two people

 

For empty weight I'd only run @ 30 in the rear, 35 up front. If you're hauling a load, (800-1000 lbs), definitely run your pressure up. I've NEVER had to put 50 psi in my tires and I hauled 2300 lbs of wet sand for 10 miles one time...

 

On the farm trucks we haul stuff all the time , 40 pounds is all we run in tires, unless it just a massive load of something

 

u-joints. this just happened to me over the weekend. i was climbing up some hills going to the mountain house, and before i got to the top i noticed a vibration under load. got to level ground again, got it up to speed, vibrates under load, stops when you take your foot off the gas, or take it out of gear. put the parking brake on, truck in nuetral, and get under there and shake the driveshaft. watch for play in the u joints themselves, not the small amount of play at the pinion. if theres no play and you still suspect the u joints or driveshaft, take it out and go driving around on your front one in 4 wheel drive.

 

Another vote for U-joints and 35psi in the tires.

 

I got this done about two weeks ago, but i'll tell you anyway

I had one u-joint that was REALLY loose and one that rusted to the point that it took a hammer to move it

lol
thanks!

 

also... I was getting ready to pull the drive shaft myself when some guy on a golf cart pulled up and said I couldn't work on my truck, against some policy or something. (I have been out wrenching on something every other weekend or so since I moved in almost 10 months ago.) So I told him I would put in my notice to leave and move out asap. (Which I had to do anyway because my lease was ending soon and I was going to move out)

 

lower your tire pressure, the pressure listed on the tire is a MAX PRESSURE...not what you should be driving around on. your gonna end up with some severe inner tire wear, and your gonna go thru your tires in like 10k....i run bfg's also, and i run 32 up front, and 30 in the rear, if i carry a load i go up to 35-37 in the rear...

 

I did that first... so I only drove 200 miles or so at high pressure

 

my truck is wierd in the fact that it feels like im on rumble strips when i let off the gas going down a hill at 70-80 mph on the freeway. I can still feel the vibration when only going 60 but much less. It will completely go away if i hit the gas and accelerate.