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Topic: Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent (Read 5820 times) previous topic - next topic

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #15 –
UPDATE.

Quote
The reason those springs broke is that they are not made well.


I don't think the steel that Ford had spec'd for the springs was of a lesser quality. I think the way the Ft Springs were designed to fit into the Crtl Arm spring cup caused the springs to break. Stress on the springs was about the same since they both broke at roughly the same length.

Due to parts being lost in shipping, impending winter weather and working out in the open I was not able to get new springs installed. So I cut both of the broken springs to the same length 14.25" then installed them along with new Crtl Arm bushings and new spring isolators. Result was more of a front end suspension drop. Fender lip to ground now measures 26.25" and there's a 1.25" fender/tire gap. The rear of the car still has the same twist. When I get some time I'll take the car to the repair shop.

XX

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #16 –
My 86 Elan sags to the drivers side in the rear when sitting on level pavement. Hopefully I'll eliminate it when I install my new 8.8 rear and four new springs.

I regard to Ford springs, while they weren't T-Birds, BOTH my 86 and 00 Taurus's broke springs. Ford even issued a recall to put sleeves on the fronts, as they would puncture the front tires when they broke!
1986 Thunderbird Elan 5.0 EFI AOD, 3.73:1 SN95 rear, 17" Mustang Bullitts w/Firestone WO Indy 500's. Future plan: 349 stroker, C9 block, forged dish pistons, Scat 9000 crank, 4340 I beam rods, ARP head/main studs, ported explorer intake, 1.72 CC RR, Vortech V2 supercharger, Mr. Freeze Meth Inj, intercooler, TFS 190 11R CNC heads (66CC), BBK shorties with 2.5" duals, 4R70W Transmission, Taurus fan.

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #17 –
Was the car ever hit in the driver side rear? The bumper alignment with the quarter panel looks a bit off.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #18 –
The other thing that can cause the springs to have an issue is the weep hole in the lower control arm spring pocket to get plugged and rust becomes an issue.  This is especially hard on cars up north where salt is used quite a bit.

One last thing to try is to loosen the bolts on the upper and lower control arm on the rear end and then torque them with the suspension loaded and level.  This goes for the front lower control arms as well if you did not already to that when you put it back together.  Torqueing the bolts up without the suspension loaded and level can cause preload and get things all out of whack.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #19 –
I too am struggling from this situation.  I was low in stock form with factory 16s and now I have a sn95 cradle with new factory sn95 springs.  My rear springs are factory height and now with 17x9s and 275 tires, I am about to cut my left rear tire!  Have tried all mentioned above.  I need to finish the car. I have a wheel lip roller so I don't cut the lip in the future but I am 1/2 lower than the other side.

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #20 –
Have you taken it to a body shop and put it on a frame machine?  Several of the Mustang folks suffer from this same issue and some of it was just the sloppy tolerances back in the day and if they all lined up it caused the car to be out of whack.  One of the guys worked at a body shop and put it up on the frame machine and it was horribly out of whack.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #21 –
Not yet.

Repairs keep popping up. The battery disconnect switch that I'd installed several years ago went bad last month and killed the 11 year old car battery. Then yesterday when I was going to get the alignment checked one of the rack & pinion hydraulic transfer tubes failed. Spewed oil all over the underside of the engine bay.  I figure the tube got damaged when I had to move the Rack while changing the Ctrl Arm bushings. This is what brought me back to the forum today. I was searching to see if there was some place that sold inexpensive transfer tubes. Google search only turned up places that were selling both tubes for nearly $50. I hate to replace the still good original Ford rack & pinion for some reman unit. But when a new life time warranty reman unit can be bought for around $85 it don't make sense to buy just the tubes for $50. Then I'm going to have to buy new P/S hoses since they too are originals and then I'll also have to clean out the P/S pump. Would not want to contaminate a new rack. I'm thankful I can do these repairs myself otherwise I'd probably have to dish out over $300 bucks at some shop.

If anyone knows where to buy inexpensive rack & pinion transfer tubes feel free to respond.

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #22 –
Have you looked to see if you can get a rack from a salvage yard off a Fox or SN95 Mustang and use those tubes?  Someone on here might have a junker laying on the shop floor they can pull off send you but I would start another thread with that in the title to get some traction.

I have reman units in both cars and have only had an issue once so that may be the best way to go and use yours for the core.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #23 –
I was just talking to my alignment guy about the sag issue, as my car has it, as well.  He suggested simply putting a spring spacer in one of the rear springs to even things out.  This seems like it would be an easy an effective fix, and avoid lots of labor and other expense.  Has anyone tried this with success, or have any reasons why this wouldn't be a bad idea?

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #24 –
Adjustable lower control arm, spacer, and coil overs have all been used.  One guy measured his wheel well to the ground and found that it was only an 1/8" difference but his bumper cover was over a 1/2" different.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #25 –
These are a good bet: http://www.maximummotorsports.com/1983-88-Thunderbird-C429.aspx

I've got the extreme duty versions in my Thunderbird.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Update by 87tbird_org_owner June 4 2017

Reply #26 –
After 3 attempts in trying to get an undamaged rebuilt R&P unit I've finally got the R&P installed and have taken car to alignment shop. The alignment settings in the attached photo show camber is not as bad as I thought back -1.6L and -2.0R verses what I initially thought of -5.0. May have to get the adjustable caster/camber plates if these camber settings cause tires to wear. Caster changed a little, not as much as my prior alignment records on car indicated. Toe reading is from me reattaching the outer tie rod ends on the R&P unit and doing the best I could. Still have to take car back to body shop for them to see why car still tilts.

Don't know if there is something wrong with the R&P unit just installed. Engine drops some 200 to 400 RPMs at idle when turning the steering wheel. Something else for me to worry about.

WARNING to those who purchase a R&P and have it shipped to your home. It probably will come damaged. I purchased from Autozone and there was nothing in the R&P box to secure the unit from flopping around. Had 2 R&P's arrive which had a crushed or broken hydraulic transfer tube.

X

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #27 –
Typically you will notice a drop in rpm when turning the wheel at idle. Did you replace the pump? Did you flush the system before installing the new rack if you did not replace the pump? What fluid did you use?

The camber is far too negative and will wear the tires as well as cause poor cornering response with the lack of caster the car has. You need CC plates no question about it.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Left Rear Sagging on 87 Tbird, Mechanic Thinks Right Frt Control Arm Bent

Reply #28 –
That camber will wear the shiznit out of your tires.  Ask me how I know.  Seriously, ask me.

Get the C/C plates, fix the camber to around -0.75 to -1.0, max out the positive caster you can get with them, I got around +4 to +4.5.  More positive caster will make the car feel more on center, and will help the car straighten out the steering after a turn.  It also greatly improves high speed stability.  Once you have the plates, install them and run back to the alignment rack.  Ask for stock camber and toe, but ask for at least 4 degrees positive caster, as recommended by the install sheet.  These cars don't specify and cross caster, so be sure to get them exactly the same, or as close as possible.  If possible, sit in the driver's seat during the alignment, if your shop doesn't allow it, ask for the seat to be ballasted with your approximate weight.