Help with loose rear suspension

[IS3FIFTY]

I can tell something is loose with the rear suspension/rear end. I can feel it when I shift gear or when I drive and release the accelerator. Like something in the suspension is loose and doesn't handle the engine torque anymore.

Before I crawl under the car to check the bushings and attachments, I wanted to ask if anyone has had this happened to them or if this is a common issue, etc...

Thanks!

 

[DaveG]

Check the structure around the rear Diff Mount....
DaveG

 

[dp]

pilates

 

[decoupe]

Is this a sudden or recent issue (ie looking for something broken) or just getting progressively worse (things loosen or wearing out)? Check any and all nuts/bolts on suspension and drive train - particular attention to the 4 bolts that attach the rear diff to the subframe plus the rear hanger on the diff to the chassis. If the car has never had any of the 40 year old bushings - something to consider refurbishing.

HTH

 

[sfdon]

Check those rear strut upper bushes.

 

[IS3FIFTY]

Cross member mount...

OK, so after poking around under the rear-end I noticed a bit of play in the cross member rubber mount on the passenger side. Looks like I just need to replace #10 on the attached diagram.
For those who have done this before, am I right that this only involves removing the link rod (#12) and the big hex nut (#11)?

How's the big pin (#7) held in place? I can't see from the diagram but I assume that it will not rotate when I try to undo the hex nut.

Finally, is this better done with the car on jacks (wheel off) or works the same with the car on on ramps? (I'm thinking which provides less load on that part of the suspension)

Thanks in advance for any tips!

 

[kasbatts]

If one bush is stuffed, the other is not far off, change both.

I'm not sure if they are possible to change when the rear end is "up" in its proper place, the problem is the 2 outer nut/bolts that hold the bush onto the cross member cant be got at (special tool for this anyone??) so I think you will need to drop the whole rear end down below the sill level of the car to get at them (was the case on my car anyway)

I haven't changed mine on a "running car" as such, only when I reassembled during the resto.
In theory it should go something like this, chime in and tell me if I'm not on the right path here guys.

Get the car up onto stands, the rear will need to be supported on the body of the car itself, not the cross member, I expect the center section of exhaust will have to be removed to allow the rear end to lower down and you will probably need to take the rear sway bar links of as well, and remove the rear springs, you will then need to put a jack under the diff head, unbolt the 2 x big nuts, remove the link rods, and remove the large bolt at the back of the diff head, at this point the whole rear end is free to drop (with the exception of the drive shaft, rear brake line and rear shocks still attaching it to the car, but you should still have enough vertical movement) I am only guessing here but if you very gently and very carefully lower the jack the entire rear end will drop down, go only as far down as needed!!, watch the rear brake line in the middle of the car, it may not be long enough to let this happen, if not I guess you will have to remove this hose and then bleed the brakes later. Lower down just enough to undo the 4 x bolts on the big bush to change it, repeat the process for the other side, when both changed bolt everything back up.

My only concern with this is that when you lower everything down off the big bolts, the whole rear end wants to "twist" and roll of the jack because of the weight distribution of the whole rear assembly, this is something you don't want to happen!

I would get some more opinions from the other guys first


Good luck

 

[Sven]

It's a bit tricky to support around this area. There are also four horizontal bolts that hold the bushing assembly to the cross member, and, a couple of these bolts/nuts are hard to access with the cross member in place. You will probably want 2-3 lift/support points. If you leave the wheel on I think it will be in the way. One support under the suspension arm (inboard of the brake rotor), one support under the cross member just inboard of the bushing that is being replaced, and a jack with good blocking at the two bolt holes to which the front portion of the #12 was attached, after you remove it (I had bolted a piece of wood cut at the correct angle to lift against).

The long bolt head has a spline fitting with body above (like the rear shock bolt to the hub).