Poly trailing arm bushings ?
 

Just ordered new Poly trailing arm bushings and SS shims from Corvette America. After removing the trailing arms and seeing how warn out the bushings were I am amazed how the car stayed in one lane at a time. But the car felt like it had rear steer after it got over 60 mph just changing lanes and rain groves on the hwy were a two hand hold on the wheel. So my question is are there any special things i need to do when installing the bushings into the trailing arms? I have done a search and can't find any info on using the poly bushings. Thanks in advance for any info.

Phil

I have poly everything in my car, except for two places:
Strut rods (heim joints)
Trailing arms (rubber, sent out for rebuild)

YMMV, but I don't think that the complex motion (like your hip or shoulder) is a good place to have a poly bushing, which are better suited for simple rotations, like control arms or your knee.

Otherwise, make sure you use the poly bushing lube, which is very sticky.

This is an alignment problem. With poly bushings it should wander less vs rubber.

If you had someone do the alignment show the before and after settings. If you did a DIY alignment then your procedure needs to be reviewed.

The T/A's tend to do some twisting as they move up and down. Rubber can 'give' a bit and allow that to happen; poly is not good for that and could be over-stressed. It would be good for the OP to hear from some folks who put poly bushings in the T/A's and how they are doing.

https://cimg7.ibsrv.net/gimg/www.cor...7064ce4402.jpg
I put in Poly's almost 20 years ago and they are still in good shape. They were made by Energy Suspension. I've heard of others failing though. And I don't baby mine at all!

JIM

I have poly trailing arms bushings. While its true there's movement in multiple directions there's also very little movement as well. With smartstruts what is there, maybe a 1/2 degree camber change above and below the center line and maybe 1/16 toe change? Eh.

To answer the OPs question: No, there really isn't anything special that you need to do as I just installed Energy Suspension poly bushings in my TAs last week. One thing to note is that you need to leave the bushing 'cups' from the original bushings in place. The included directions make this very clear so I will not go into detail.

Other than that, use lots of the supplied bushing lube (as was mentioned above, it is very sticky. Wear gloves) and a few gentle taps with a rubber/plastic mallet are all that is needed to seat them properly. Getting the original bushings out was WAY more difficult than installing the new poly bushings.

I just ordered Energy Suspension poly bushings for mine yesterday from Summit. This will be my project next week on my vacation.

Do some research on the C-2 forum. Many, members, including me, have had to replace them after they turn to glass and fall out. I have replaced sets on my 66 and 68. I have also replaced a few sets on my friends cars. For some reason, side pipe cars make the situation worse. Jerry

Thank for your reply I picked up the vett last September and have been working on getting it road worthy ever since I so far have removed the pedal assembly and rebuilt, removed the A/C and heater system and flushed the entire A/C system after the PO had total failure of the compressor and filled the system with small bits of brass and steel rebuilt the VIR and recharged with R12, rebuilt the heater doors seals and vent door seals. I am just getting to changing the bushing in the suspension both front and rear. I replaced the completely worn out strut rod bushing with poly and the rear spring cushions with poly. I have not had the vett on an alignment rack as of yet but will do so after the T/A bushing replacement. In total since acquiring the car i have put 50 miles on it of which 20 were the trip home the rest were short test drives after each repair. I plan on replacing the shims of the same thickness in the same places as when i took it apart to get to the alignment shop. My first priority is the car must be safe and reliable as when completed it will be given to my wife as she has always wanted C3 since she was a teen and was given a ride in one by a family friend. I am sure as work go's on I will have more questions and am total amazement at the knowledge base and help given on the forum freely. Thanks again for the help

I am using "Prothane" brand poly black everywhere in my 78. Used to track days for the last 5 years.

https://cimg3.ibsrv.net/gimg/www.cor...6565bdc3fe.jpg

Don't listen to the naysayers who probably have never used poly for anything. And even if they do fail in the t/a years down the road, they'll be far easier to repair/replace the next time around over aftermarket rubber bushing which by the way have had problems also.

I used Energy Suspension poly in mine, both strut rods and trailing arms, did over 50,000 street and track miles over 4 years. Pulled them out as I decided to put in heim jointed struts rods and Global West trailing arms, the poly bushes were still completely fine.

An additional quick note on poly. The rubber trailing bushings on my 68 were good after 40 years. I changed them out for performance purposes with poly. The poly turned to glass and fell out after less than two years. Thinking I got a bad set of poly bushings I installed them in my 66. They lasted less than a year and also broke apart. That's why most shops that install them will not offer a warranty on them. The good news is that replacing them the second time around is easier because the parts should not be rusted out. Thank god I have a lift and air tools to make the job easier. As stated above, the C-2 forum is littered with instances of failure. To each his own. Good luck. Jerry

Just curious, did you use Energy Suspension, Prothane, or the "house brand" bushings from the now defunct, VB&P??

I ordered the Prothane brand, waiting on the big brown truck to arrive will be about a week to get from PA to Reno NV then install will begin. Trailing arms are off the car and new e brake shoes have been installed. The wait is killing me, I wish there were some place on the west coast to get parts at a decent price but I have not found them yet.

Phil

If you can get a part number, it's often worth checking the big speed shops (Jegs, Summit Racing), or Rock Auto. Summit has a retail store in Sparks, NV (I don't know if they ship from there, too), and Rock Auto drop-ships from all over the place. Certain things, common engine and suspension parts in particular, don't need to be sourced from a Corvette-specific vendor.

I have poly bushings on my 68 convert. No problems.

One additional thought on the twisting motion inherent in the C2-C3 trailing arms. The arms twist + - about 5°, because of the strut rod configuration used on these cars. The result is trailing arms twist as they go up and down. The C3 actually has less camber change than the C2, but both twist the trailing arm as they move in an arc. If you switch to a Smart Strut setup the trailing arm camber change is about 1° as it moves up and down. By the way, the strut rod pickup point on the rear spindles also moves in an arc causing the strut rods to twist.

I installed poly bushings in my '73 back in the 90's when I was autrocrossing it. I also installed a Smart Strut setup I purchased from Dick Guldstrand back then. It used Heim jointed strut rods like Global West currently sells. The back of the car always stays planted when autocrossing as aggressively as the car will handle. Poly's are still in there and doing just fine... so far. :D

Of course the ultimate solution would be Heim's in both locations. :thumbs:
https://cimg4.ibsrv.net/gimg/www.cor...c7c2364ef3.jpg
Good luck... GUSTO

I got one set from Van Steel and one set from VB&P. When they failed in my 66, it was exciting to get the car home. Jerry