Timing Bushings when lowering (How to)
 

This has been a popular topic lately and it seems to be very misunderstood as well. Why and when do you "time" your bushings? This isn't a new practice, it has just been given a new name recently. We have always referred to it as re-clocking or re-indexing the bushing. In the following post I will explain the whens and whys of this procedure and hopefully put to rest the mystery that surrounds it.

The majority of suspension components hinge on rubber bushings. All bushings have a center steel sleeve (or ferrule, compression stop, etc.) that prevents you from over-tightening the bolt and compressing the bushing. The sleeve also provides an established width for thrust loads on the bushing to minimize bind. These inner sleeves are actually bonded to the rubber bushing and, in many cases, to an outer sleeve as well. When this connection is tightened, the sleeve remains stationary in the mount while the suspension component rotates by twisting the bushing.

http://www.bmrsuspension.com/ForumImages/IMG_9201.JPG

For years we have told our customers to tighten all suspension components with the vehicle at rest and the suspension loaded. This means that the vehicle is at ride height (static height), not with the suspension hanging. Tightening a bolt with the suspension hanging puts the bushing in a pre-loaded state since the bushings will already be "twisted" when the vehicle is set to static height. This can create irregular ride heights, premature bushing wear, and even inconsistent handling tendencies.

Lowering your car creates the same problem. All of your bushings are already tightened in the OE position. When you lower the car, the suspension rotates to the new lowered position while your bushings are still "clocked" in the original position. Loosening the bolts and bouncing the car a few times will "re-clock" or "time" the bushing to the new position.

So which bushings do you need to re-clock? Basically every component in the front and rear suspension that rotates on a rubber bushing. This includes the following:

FRONT:
Inner control arm bushings
Inner radius rod bushings

REAR:
Inner and outer toe rod bushings
Inner and outer trailing arm bushings
Inner control arm bushings
Lower shock mount bushings
Rear upper control arm bushings

With the vehicle resting on the suspension, loosen these bolts up loose enough to spin the nut by hand. Bounce the car up and down to pop any sticking bushings loose from the mounts, then re-tighten the bolts.

http://www.bmrsuspension.com/ForumIm...0Underside.JPG

http://www.bmrsuspension.com/ForumImages/RearBolts.jpg
http://www.bmrsuspension.com/ForumIm...RONT_BOLTS.jpg

Certainly this is not an easy task to perform at home. Getting the car up high enough to access these bolts while keeping the weight on the tires definitely requires some work. Many are using transitioned ramps to get the car high enough. Regardless, after installing springs, an alignment is necessary to correct toe and camber. This means that not only will the car already be on a drive-on lift but most of the bolts will already be loosened for adjusting the alignment. It doesn’t take much more effort from your alignment technician to loosen a few more bolts while he is setting the alignment.

We have seen cars change ride height by as much as 3/8" by simply re-clocking the bushings after a spring install. In a multi-link suspension such as the Zeta platform, this condition becomes even more pronounced because of the multiple links. More links means more bushings and more bushings means more potential for pre-load if not setup properly.

In summary, re-clocking the bushings should be as much a priority as aligning your car after a spring install. Hopefully this has been helpful to those that were not understanding why or how to do this procedure.

Awesome! Thanks for the great post.

Wow, OP, great post! :respekt:

My only question is, during assembly at the factory, the weight of the car is not on the suspension. Does that mean that, from a performance/longevity standpoint, all vehicles would benefit from "re-clocking" the bushings?

Great writeup BMR guy!

And I can attest to the absolute need to "Time" the bushings after a ride height alteration.

I installed the Pfadt drop springs and balance bar on my car last weekend. Today was the day to get the bushings "timed" and the 4 wheel alignment completed.

On my way to the shop for alignment I was beginning to think I'd made a mistake by lowering the car because of the ride quality I was experiencing. I knew there would be a slight trade off of ride compliance for handling improvements but the ride was much more harsh then I'd expected.

Once on the rack for a while, after timing but before aligning, the technician asked me who manufactured the spring package I had and who installed them? I immediately thought something must have been wrong. But to my relief he said that the drop was perfectly square side to side and just right front to back. (slightly lower in front then in back) He stated that the rear settled almost 1/2" after the bushings were timed!

Those bushings must have been under quite a bit of preload to hold the tail of the car up as much as a 1/2"! The tech wanted me to take him for a ride to make sure everything was to my liking before he signed off on the job and as soon as we wheeled out of the parking lot I could tell the difference in the ride quality.

Yes it still rides a bit stiffer then the factory set-up but the harshness that I felt on the way to the shop was gone! I LOVE the way the car looks, feels and takes the curves.

People......... if you alter the ride height of your car, take the time or pay the price to have those bushings "timed". The difference is night and day!

:headbang:

I was wondering what this timing was all about. Thanks for the explanation.

Didn't time mine with the Hotchkis setup or so they said. rides great, no "sticksion" from the bushings or bad ride and full fluid vertical movements. Only std abruptness on bumps from any lowered car with less travel but not much and well cushined from the v6 shocks . Lucky I guess.

I don't know. I have a feeling you may not know the difference.

If you had it done I bet you would feel it afterwards. Originally I didn't have it done and then when I had my 20x9 put on front I decided I might as well align and have it timed this time. I could feel the difference. It's not like my car rode horrible or anything but once it was done I could feel a slightly less bounce to it. Not day/night differnce but enough to feel.

No one says you have to do it but it's like adding headers without a tune. You'll definately benefit from having it done.

anyone know the torque specs on all of those that are required for the 'timing'?

got quoted an extra $50 to do this. Does that sound reasonable? Wish I could do this on my driveway.


And thanks soo much for this thread as it is EXTREMELY HELPFUL!!!

Excellent post Brett.

That's probably about right...especially if you don't have the means to do it yourself. I would say an extra .5 - 1 hr worth or work.

thank you very much, ill have them do that then :chevy: :w00t:

Now to fix that right front pulsing creek noise :mad0259:

SOLD! Will have them do this for sure.


PS probably going to get shot if you guys knew where I was taking it for an alignment.....FORD yes thats right. Sadly its the only shop I trust around here. Knowing my dealer, theyll make me pay and not even do the work let alone probably damage something else on my car

Thats because it was your image that inspired me to write this thread. There is no shame in admitting that. This topic is so misunderstood that a simple picture of the bolts was not enough. It was a great starting point for a more detailed thread. We talk people through this on a daily basis but simply pointing out the bolts doesn't explain the how's or why's, nor what each component is...