Rear Control Arm issues

I don't know if this is normal or not . . .

I'm redoing the frame on my 70 Lark. Had original 10 bolt rear, swapped it out for a 12 bolt from a 72 Chevelle/Monte Carlo.

Now I have Global West adjustable upper control arms, but something doesn't seem right where they connect to the rearend housing. The control arm is actually touching the housing with new rubber bushings installed, and the adjustable arms set to stock length.

Anyone have a similar problem, or advise?

 

ok i did the exact same set up as you have but on my 71 lark, if you can post a few pics I'm sure its a simple fix. I also installed the total rear and front globalwest tubular suspension and also switched out my 10 bolt and installed a 12 bolt posi out of a 72 chevelle(great minds think alike, EH). I can post some pics of my setup tomorrow sometime when i get to my office computor. Don't sweat it, it'll work out. Gord

 

I'd post a pic, but my camera is broken at the moment. If you can get a pic up, I can show you exactly what I'm talking about.

 

Do you mean the axle housing or the outer part of the bushing?

 

The bushing barely clears the housing when installed correctly, but the forked end of the control arm that goes around the bushing contacts the center section of the differential. It still installs, but it looks like it's rubbing on the differential!

 

This is what I use and it looks like Edelbrock was concerned about this and added that rubber bushing to keep things centered.

 

John ...show us a pic if you could ....


just in case ..is the bushing all the way in ...?? and also make sure they are inserted in the correct direction ...

 

ok heres a few pics of my setup which should be exactly the same as yours.

 

i dont see the problem but try to load frame like it has a 1000 pounds of body
to hold up
the angle of the arms will change,also you shouldnt tighten until you have all body weight on it anyways

 

Going by Racenu's photo (thanks), this is where i'm having clearance issues.


I'm going to try to refit it sometime tomorrow, and see if I can get it to clear. It just seems like the chassis is really stiff at the moment; hardly any play in the springs or shocks. My guess is that somehow it's binding up, or twisted funny???? The bushings are installed correctly (they only install one way, cause it wont clear the housing to install the other way), and are at the correct depth, so it's not the bushings.

I'll get some photos tomorrow afternoon as well.

 

When I installed my bushing in the diff i did the easy side first, I made a special tool and cranked that sucker in all the way and went to do the other side and realized my tool wasn't going to work, I then realized I had the bushing in all the way and was only suppose to go half way in DOH Oh. This was just one little boo boo on my part in the whole suspension installation process. Good luck John

 

It's only supposed to go up to the ridge in the bushing . . . or so i think, cause that center's the control arm over the housing. Just common sense. I think I'll be OK, if I still have clearance issues after today, I'll just have to modify the carrier section of the differential. God I hope I don't have to do that!

 

Yep Hutch just up to the ridge, that'd suck if you have to modify the carrier for sure?

 

John,
After looking at this on my own car I have no idea how you can even be close to having interference. I would really like to see pictures so I can understand the problem.

With the GW control arms you should not have a binding problem. Especially with the rubber bushing you are using in the upper arm. To test for binding set your car on jackstands with the rear axle hanging. Then place your floor jack under one side of the axle and jack it up carefully. You should be able to jack one side up at least a foot. Should be very smooth with no noise. Ideally this test is done without springs and sway bar but you should be able to see what is going on with them.

 

have you tried fliping it over or switching sides?
maybe one side is clearanced for that

 

I have a 12 bolt. As far as I know they are interchangeable. Canadian Larks used a 12 bolt.

 

on my 70 with an 8.2 rear, I just swapped a chevy 12 bolt in yesterday and the factory uppers fit fine with no issue. not sure about aftermarket, I do know that one of the bushings installs close to the top of the pumpkin, but no problem with the arms.

 

Thare was a difference between the 10 bolt and twelve bolt upper arms.
The twelve bolt arm for the drivers side had a notch cutout for clearance at the housing.
Look at the GW arms to see if one has a diiferent shape. You may have to swap them.

 

Well, I was working on it today . . .

I basically didn't get anything accomplished with the suspension; I've got bodywork on my mind, but I have a question:

I didn't see that there is a different part number for the upper arms on a 10-Bolt vs. a 12 bolt . . . Can anyone confirm this? Seems to be that there is only one kit available, or so says Jegs, and Global West's website.

I couldn't get a picture of it . . . seems I've conveniently misplaced my camera . . . :rant:

I should hopefully be able to get out there this weekend some time to get a better look . . . i didn't try swapping the arms, or look that closely at them, so maybe there is a section of one arm that is clearanced for this problem. I'll try looking a little harder, and I'll swap them and see what happens.

I was wrong about bind . . . definitely not bound up at all. Took the springs out, and it has tons of travel from side to side, up and down.

With all that being said, It's 3:30 AM here, and I gotta get some sleep!

P.S. --- Doug (sailbrd), I'll get a photo of it when I find my camera to show you exactly what I'm talking about