Polyurethane Lower Control Arm Bushings

Is there a possibility that a piston ring compressor designed for a small engine like a chain saw may work in this application? With lots of lubrication. Just a thought.

put the bushings in the freezer for at least a couple of hours (overnight would be better) and before you take them out of the freezer, put the sleeves in the oven for a few minutes to heat them up (about 250-300 degrees) they only need to stay in for 5 minutes or so. then grease the bushings and they should slide right in, no muss no fuss

Fredo said:

I tried the bushing in the freezer trick and it only partially worked
I put the bushing in the freezer overnight and then put the sleeve in the oven at 300 degrees for 5 minutes,then gresed the frozen bushing and tried to press it in with the vise. It went in 3/4 of the way and then stopped, the poly bushing then started to mush down and would not go in any further.
Please help, am I doing something wrong?

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you may have already made the bushings too soft by trying to force them in. try it again but leave the sleeves in the oven for about 15-20 minutes, if that doesn't work you may have to order new bushings

You didn't say how you are trying to press them in but I'm assuming with a vise or press. What about trying to pull them in using a bolt through the middle instead? How about using some hose clamps around the exposed portion to keep it from enlarging and taking them off as it goes in?

I'm curious why you are installing them in the first place though since they are generally not recommended anymore because of the bind caused by the arc that the strut rod makes the lower arm travel in?

68Restoman

68restoman - could you elaborate about why they're not recommended anymore? i hadnt heard this. is there another alternative out there?

3spd on floor said:

68restoman - could you elaborate about why they're not recommended anymore? i hadnt heard this. is there another alternative out there?

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This came about when people who were running poly in the lowers and in the struts started having catastrophic strut rod failures. What they realized that using poly in both spots causes severe bind and puts alot of lateral pressure on the strut rod near the bushings (they tend to snap right where the threads start).

It makes sense if you think about it. The lower arm has a straight up/down pivot point. However it's constrained by the strut rod which is at a 45 degree angle to it so the effect is that the lower arm actually travels in an arc because it is pulled forward by the strut rod as it goes further from a neutral position. If you've ever tried to move the lower assembly by hand it's pretty obvious, it binds at the top and bottom of the travel and the farther you go the more it binds.

I tend to follow the advice of the top road racers and open track guys since they live this stuff. What they say is if you want to run poly, only run it in the strut bushings, never in the lower control arms. If you do run poly in the strut rods, make sure you put the cup washers with the cup facing away from the bushings not cupping around them. This allows more freedom in movement. I personally would never run poly in either spot myself after seeing a broken strut resulting from poly in the struts.

The only way to go really is to run spherical bearings also known as monoball bushings. These are ball and socket bearings that allow some sideways movement. Examples include TCP and Global West but alot of guys are making their own (including me) from the stock car parts catalogs.