I recently replaced my rubber bushings in my lower control arms of my ‘95 XJ, 4.0, Auto trans, 4x4 172k miles with polyurethane bushings. I haven’t done the upper arms yet, but I have the poly bushings to do them. The longer I drive the Jeep with the squeaking, grunching, rough riding poly bushings in the lower arms, the more I’m thinking about replacing the lower arms with new rubber-bushings-installed arms.

Is there a way to quieten down the poly bushings? I did grease them upon installation, but that didn’t keep them quiet for more than about a month.

Is there an up side to poly bushings other than being easy to install? Longer wear than rubber? I’m not finding any advantage yet. The part that tops it all off is my old rubber bushings weren’t really all that bad. They had hardened with age, but weren’t terribly worn. I thought they were the cause of some poor handling, but that was mostly tires. If I’d bought new tire first, I probably wouldn’t have changed out the bushings.

By the way, for what it’s worth, I did figure out an easy way to remove the rubber bushings from the lower control arms. 2” PVC coupling or PVC “T” and a piece of 1/2” all thread about 14” long with big fender washers. Put the all thread through the bushing, put a nut and washer on the all thread, put the 2” PVC on the opposite side of the control arm and put on another washer & nut. The washer has to be larger that the 2” PVC. Start tightening the nut on the PVC side. If the bushing doesn’t pull right out, leave the pressure on it and heat the metal of the control arm with a propane torch. It won’t take much heat and the bushing will turn loose. It took me about 10 minutes to remove both rubber bushings from one control arm. Only had to heat one end.

 

I much prefer rubber. They bounce back after being compressed
and last longer, besides being more comfortable. Poly seem firm
and give good control at first, but over time they compress and
don't retain their shape and will need replacing.

 

I've used poly bushings alot. The key is to lube them alot. Way more than you would think they need.

Not saying they are better than rubber.

 

Poly bushings need to be lubricated with synthetic grease. That will at least get rid of the noise

 

I was under the assumption that all rubber bushings need to be pressed on while poly can be put on by hand. They make a poly lube that comes in an 8 oz tub for 10 or 12 bucks and works well. Way back when, i went all poly because it would have cost a fortune to have the machine shop press on bushings for all my leaf springs and control arms and such

 

Dust, dirt and mud are not a good combo for a bushing that needs greased to be quiet...And if you're into moderate to hard wheeling and don't want to be under the vehicle always checking components, those rubber bushings absorb more shock than you realize...On the plus side they're definitely easier to install, much less deflection so better geometry by default...But considering how long the rubber bushings last compared to the poly {I couldn't get much past 20-30,000 without noticeable play even mostly street} the only place I use poly anymore is the sway bar bushings..

 

Poly bushings are pretty close to mandatory for any vehicle that is going to race on pavement. Compared to rubber, they introduce far less play into the suspension, which translates directly to better handling.


And that, ladies and genetlmen, might help you understand why they have a reputation for being better than rubber. They are better than rubber, in that application.


Daily driver? Off roading? Well, since the requirements are different for those applications, that might be a different question. Maybe?

 

I greased the heck out of these when I installed them. That resulted in about two months of use before the squeaking began. The rougher ride off road began on day one. Since I don’t do a lot of racing on pavement in a ‘95 XJ, I’m going to start the transition back to rubber....

 

All poly bushings will give increased performance by limiting the amount of vibration and compression absorption. Having said that, poly bushings come in various hardness. The hardest won't give hardly at all and produce the rough ride you are having. Another thing, what is the angle of your front links. If you are lifted a bunch, that alone will increase the harshness of the ride. I think we might need some more info on this

 

I've used poly bushings for years on various vehicles and found that torqueing them to minimum specs keeps the noises to a minimum if not completely eliminating them.

I recently either saw a video or read somewhere that wrapping the poly bushings with thread tape before greasing them then installing will eliminate noise.

 

I resolved squeaky bushings by upgrading to the greasable bolts, they have alamite fittings on the head. It had eliminated all squeak from my rear shackles with poly bushing. They are also available for control arms shttps://www.summitracing.com/parts/tgi-111306-1-kit?seid=srese1&gclid=CjwKCAiAlNf-BRB_EiwA2osbxdo9jAFvCofICkgec2THCXsec0iN5QPocBxBUV zU4Ds5Irnneo3VFxoCbOQQAvD_BwE
I also drilled a few small holes in the metal sleeve inserts so the grease would travel to the bushing underneath.

 

Very little lift, 1” spacer on the front and a leaf added in the rear. I’m probably near stock height before spring sag.

 

Yep. That's what they do. #1 complaint about poly bushings.