Rear Suspension Alignment - Page 2 - ZR-1 Net Registry Forums

GOLDCYLON · 12-20-2012

After replacing the bearing and if required the rear spindle Id suggest a 4 wheel thrust alignment.

ZR1North · 12-20-2012

Good suggestions guys - thanks. Re the camber, here are the before and after alignment readings (for the rear):

Before Alignment
Left Rear Camber: -.5 Right Rear Camber: 2.4 (could see it tilted out at the top)
Left Rear Toe: -.15 Right Rear Toe: -.41

After Alignment
Left Rear Camber: -.1 Right Rear Camber: 0.0
Left Rear Toe: .02 Left Rear Toe: .03

Hib Halverson · 12-21-2012

If your rear wheels are offset 1/2 inch, that huge.

Two things to check and you may need the uniframe dimensions which are in the factory service manual.

First, you need to see if the rear frame rails are bent in the areas where the rear cross member is attached.

Second, you need to inspect the rear crossmember, which also is the rear diff cover to make sure it's not deformed.

For both wheels to be offset, since the axle shafts and the strut rods locate the wheels and both connect to the rear axle housing, that housing has to have moved sideways. The only way that can happen is if the frame is damaged, the rear cross member is damaged, the rear xmember mountings are damaged or some combination of all that.

Once you determine what parts of the car's rear structure have been damaged and make repairs, then move onto any damaged trailing arms, lateral links, bearings, hubs and etc. Once you have those items addressed, them do you alignment.

You musta whacked that curb a good one, that's for sure.

ZR1North · 12-28-2012

Update: Took the right side upper and lower spindle control rods off and can now see bends that I couldn't see while the components were on the car.

Going to install the new control rods, new bearing assys, and loosen all the bolts where the rear diff mounts to the body - hoping the new parts and slight pull on the rear diff will restore things to normal before heading for another alignment.

Learning about polyurethane vs rubber bushings in the process. Seems like polyurethane has more merits than I thought.

Thanks for the advice!

batchman · 12-28-2012

Glad you found your culprit, and that it was something readily serviced.

Quote:

Originally Posted by ZR1North

Learning about polyurethane vs rubber bushings in the process. Seems like polyurethane has more merits than I thought.

Poly does have some disadvantages though. It will cold flow so if it's in a stressed location it won't keep a perfect shape, and it gets pretty squeaky if not set up to be lubed and kept after.

Harder rubber is a better choice for the street, of course that's not so easy to do. Delrin is a more durable choice but will be more harsh.

Cheers,
- Jeff

12-20-2012	#11
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,154	Re: Rear Suspension Alignment After replacing the bearing and if required the rear spindle Id suggest a 4 wheel thrust alignment. __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V

12-20-2012	#12
ZR1North Join Date: Feb 2007 Location: Ann Arbor, Michigan Posts: 568	Re: Rear Suspension Alignment Good suggestions guys - thanks. Re the camber, here are the before and after alignment readings (for the rear): Before Alignment Left Rear Camber: -.5 Right Rear Camber: 2.4 (could see it tilted out at the top) Left Rear Toe: -.15 Right Rear Toe: -.41 After Alignment Left Rear Camber: -.1 Right Rear Camber: 0.0 Left Rear Toe: .02 Left Rear Toe: .03

12-21-2012	#13
Hib Halverson Join Date: Jun 2005 Location: CenCoast California Posts: 899	Re: Rear Suspension Alignment If your rear wheels are offset 1/2 inch, that huge. Two things to check and you may need the uniframe dimensions which are in the factory service manual. First, you need to see if the rear frame rails are bent in the areas where the rear cross member is attached. Second, you need to inspect the rear crossmember, which also is the rear diff cover to make sure it's not deformed. For both wheels to be offset, since the axle shafts and the strut rods locate the wheels and both connect to the rear axle housing, that housing has to have moved sideways. The only way that can happen is if the frame is damaged, the rear cross member is damaged, the rear xmember mountings are damaged or some combination of all that. Once you determine what parts of the car's rear structure have been damaged and make repairs, then move onto any damaged trailing arms, lateral links, bearings, hubs and etc. Once you have those items addressed, them do you alignment. You musta whacked that curb a good one, that's for sure. __________________ Hib Halverson Technical Writer former owner 95 VIN 0140 current owner 19 VIN 1878

12-28-2012	#14
ZR1North Join Date: Feb 2007 Location: Ann Arbor, Michigan Posts: 568	Re: Rear Suspension Alignment Update: Took the right side upper and lower spindle control rods off and can now see bends that I couldn't see while the components were on the car. Going to install the new control rods, new bearing assys, and loosen all the bolts where the rear diff mounts to the body - hoping the new parts and slight pull on the rear diff will restore things to normal before heading for another alignment. Learning about polyurethane vs rubber bushings in the process. Seems like polyurethane has more merits than I thought. Thanks for the advice!