I'm trying to chase down some vibrations I am feeling. I feel them underneath the truck at speeds from 55mph up in to the 70's... Nothing crazy, just a nice, tight vibration.
At first thought, I thought of the Rear Driveshaft, because that is what it felt like. I crawled under the truck with my trusty Lincoln Grease Gun and gave the rear driveshaft a wiggle. I could feel a slight bit of play at the Slip Joint. I put some grease in the slip joint until I could see the driveshaft bump with a pump from the grease gun. I went ahead and gave the Double Cardan Joint a few shots of grease as well in each of the two U-Joints. I also went ahead and greased the Slip Joint on the Front Driveshaft while I was down there.
Test Drive: there was an ever so slight improvement, but the vibes were still there.
On to the next possibilities. As some of you guys know, when I first bought the truck, the steering was all jacked up and the front shocks were blown. The steering rack had a lot of play in it. Well, now I have replaced the steering rack, Lower Ball Joints, Shocks, etc... I got the truck aligned afterwards. When I first drove it, I could feel a lot of vibes in my steering wheel.
Well, I could see some inside camber wear on the front tires, which are pretty damn new, Goodyear Tracker 2's. So, after it was aligned and all fixed up, I rotated the front tires to the back(on the same side they were on). This cleaned up the steering wheel vibes.
So, now I'm thinking it could be the tires. Obviously, they need to be rebalanced; One, because tires obviously need to be rebalanced every so often, Two, because I have no idea who balanced them before, and Three, because I feel that the wear on the front(now the back) tires could have worn them out of balance.
However, what makes me think that it isn't the tires is that it only comes around after I get above 55-60mph... I would think that I would feel the vibrations more often if it was tire related. I guess if it is tires, once you are going that speed, the tires change shape from which they are when you are only going 25-30mph....
If it's not tires, Do 4Runners have any idiosyncratic little things that cause vibrations? Going back to my Jeep days, there were lots of things that could change ever so slightly and you would get Death wobble in your steering, or you would get rear driveshaft vibes... Hell, my rear leafs sagged over time and ultimately a change in 1/4 inch height gave me rear d/s vibes.....
I did put 1.5" rear spacers and 1" spacers on the truck when I put new shocks on it.
Being that it is a linked suspension and not leaf sprung, this usually accounts for driveshaft angle in the arc of the suspension, so I wouldn't think it would be rear pinion angle. Obviously the front 3rd member doesn't move with a lift, so the front pinion angle wouldn't be suspect. Would a 1" lift bring vibes to the front C/V axles?
I wouldn't think the c/vs would be the problem really.. Or else I would feel it more I would think...
Its not really vibes so much as a steering shimmy from 55-75....
I have
NEW OEM Toyota Steering Rack
NEW OEM Toyota Lower Ball Joints
Newish Outer Tie Rod Ends....
The new rack obviously has new OEM Rubber bushings in it... On the passenger side wrap around bushing ive tried the OEM rubber and a Poly bushing.. but it has made no difference...
The Outer Rod ends look OEM, they are definitely fresh.. But they could be parts store rebuilt units I suppose... Id hate to change them for no reason though...
My Upper Ball joints seem to be good, no grease squirting out... no play in them
My wheel bearings seem to be good. Absolutely no play in them... No bearing roar typical of when a bearing starts to go bad...
I do have some bad sway bar bushings that are clunking... but that shouldn't affect the steering... just sway/lean...
My Rag Joint, the little rubber joint/bushing between the steering rack and the steering is cracked and could use a replacement... I really wouldn't think that would be the cause though....
This thread hasn't gotten much attention, Does anyone have any ideas????? do 4runners have any common causes for this????