Clocking bushes when lowering VF's.

[RevNev]

Needing a hit to satisfy my 40+ year serious addiction to tampering with cars meaning any car of mine can't remain stock, I'm in the process of giving my recently acquired MY16 SV6 wagon a subtle tweak. Being raised with the idea that you're a bit of wan%$r trying to make an SV6 look like an SSV Redline, the car will retain the SV6 look but a better version of the SV6 in appearance and drivability.

405mm from the centre of the wheel to the guard is no good (overlander style), so I've fitted King SL's in the front and RLHD's in the rear that moderately lowers a V6 25mm reducing the ride heights to 380mm. Particularly in the front end, the lower control arm and radius rod bolts are tightened at stock ride heights and when lowering the ride heights, the bushes distort. Consequently, I "always" loosen the bolts at the revised ride heights when lowering a VF that's a relatively simple and essential process that I don't see many do that often and they should particularly suspension specialists for most part are too lazy and can't be bothered!

Even lowing the car only 25mm and loosening the lower control arm and radius bolts, I could hear the bushes "twang" into their revised clock location and the bushes rotated 5 or 6mm from their stock ride height position. Here are the bolts (pictured below) that need to be loosened and retightened, and you'd be surprised how far the bushes move to eliminate distortion from lowered ride heights.

 

[RevNev]

Furthermore to lowering VF's, I think the 380mm ride height (King SL's on the front of a V6 and L's on a V8) is a good practical height where the car doesn't look lowered but doesn't look high either and still clears speed humps and reasonable driveways. Probably the ride height the SV6/SS and Redline should've been stock and works with stock shock lengths without bump clearance issues.

Another good subtle mod on stock wheels is increasing the offset from +48 to +36. It's not particularly noticeable but places a 245 tyre in the guard where it should be and takes the "elephant ear" A9X Torana look away from the car with guard flares and skinny tyres. It's a bit naughty that mod, so we'll leave it to your imagination how it's done!

 

[Smitty]

Needing a hit to satisfy my 40+ year serious addiction to tampering with cars meaning any car of mine can't remain stock, I'm in the process of giving my recently acquired MY16 SV6 wagon a subtle tweak. Being raised with the idea that you're a bit of wan%$r trying to make an SV6 look like an SSV Redline, the car will retain the SV6 look but a better version of the SV6 in appearance and drivability.

405mm from the centre of the wheel to the guard is no good (overlander style), so I've fitted King SL's in the front and RLHD's in the rear that moderately lowers a V6 25mm reducing the ride heights to 380mm. Particularly in the front end, the lower control arm and radius rod bolts are tightened at stock ride heights and when lowering the ride heights, the bushes distort. Consequently, I "always" loosen the bolts at the revised ride heights when lowering a VF that's a relatively simple and essential process that I don't see many do that often and they should particularly suspension specialists for most part are too lazy and can't be bothered!

Even lowing the car only 25mm and loosening the lower control arm and radius bolts, I could hear the bushes "twang" into their revised clock location and the bushes rotated 5 or 6mm from their stock ride height position. Here are the bolts (pictured below) that need to be loosened and retightened, and you'd be surprised how far the bushes move to eliminate distortion from lowered ride heights.

View attachment 252556

View attachment 252557

hmmmm....

you tighten these back up to factory torques with their normal suspension load on them? and then do a 4 wheel alignment?

important .. as you have changed their static position from the original factory spot and you have to allow the bush to move
when the suspension goes UP and DOWN. If you don't (and suspension shops don't do this either) you will just chop out bushes

 

[dassaur]

Even lowing the car only 25mm and loosening the lower control arm and radius bolts, I could hear the bushes "twang" into their revised clock location and the bushes rotated 5 or 6mm from their stock ride height position. Here are the bolts (pictured below) that need to be loosened and retightened, and you'd be surprised how far the bushes move to eliminate distortion from lowered ride heights.

Thanks RevNev
As an amateur mechanic, do you think the rears need to be done in the same way, and if so, which would be the appropriate bolts?

 

[Skylarking]

Doesn‘t the service manual make a point of stating that suspension components need to be loaded by lowering the vehicle onto its tyres before the bolts are torqued up?

Regardless it’s a good reminder that such is required else the suspension bushes will just chop out sooner rather than later…

PS: I hate TTY bolts

 

[wetwork65]

(off on a tangent as usual).
Thanks for the two photos. I thought my cars had an unusual amount of surface corrosion in hidden areas, due to living near the beach, but mine look much the same as yours.

 

[dassaur]

Doesn‘t the service manual make a point of stating that suspension components need to be loaded by lowering the vehicle onto its tyres before the bolts are torqued up?

Regardless it’s a good reminder that such is required else the suspension bushes will just chop out sooner rather than later…

PS: I hate TTY bolts

Yes definitely, however I had only been redoing the bolts that I undid to get to various components.

 

[losh1971]

PS: I hate TTY bolts

Which suspension bolts are TTI? I haven't read that in the manual.

 

[RevNev]

hmmmm....

you tighten these back up to factory torques with their normal suspension load on them? and then do a 4 wheel alignment?

important .. as you have changed their static position from the original factory spot and you have to allow the bush to move
when the suspension goes UP and DOWN. If you don't (and suspension shops don't do this either) you will just chop out bushes

Yes, rubber bushes pressed into a control arm distort as the suspension moves but should be distortion free at the static ride height. If they're not, the additional distortion through suspension movement, can exceed their design limits and wear the bushes out prematurely. In some cases, distorted bushes can cause uneven ride heights from left to right.

Clocking bushes needs to be done on a 4-post hoist or these Race Ramp chocks (pictured below) I use to do it on the floor. For wheel alignments, I do a manual alignment as we do on race cars with a camber/caster gauge, string line and trammel bar for toe. I've found on the front of a VF as a general road car, 0.5 degrees camber and 1mm toe in is best for good tyre wear. On the rear, 0.5 to 0.7 degrees camber with 2mm toe in works well.

 

[RevNev]

Thanks RevNev
As an amateur mechanic, do you think the rears need to be done in the same way, and if so, which would be the appropriate bolts?

Only the toe arms and camber bushes on the rear as the other bushes are ball jointed and freely rotate. I'll picture the rear soon!

Doesn‘t the service manual make a point of stating that suspension components need to be loaded by lowering the vehicle onto its tyres before the bolts are torqued up?

Yes it does!

I thought my cars had an unusual amount of surface corrosion in hidden areas, due to living near the beach, but mine look much the same as yours.

This SV6 Wagon was a country car and had a bit of red dirt underneath that I've cleaned off a bit with some CT-18 and pressure washer. Country cars are usually pretty good mechanically providing they're not peppered with stone chips and fortunately only had a couple of small stone chips on the front bumper.