75 280 Rear Suspension Work & Disc Brake Conversion (MilkFab)

[HusseinHolland]

Started pulling apart the rear suspension after work today. Had to remove the exhaust first - since it's all one piece from the DP flange to the tailpipe, I cut it behind the cat. I'll add a junction there - maybe a V-band, or just a sleeve clamp. Ultimately the whole exhaust will be custom with the VQ35DE anyway. Looked over the undercarriage in general since this is the first time I've been under the back end

Control arm bushing are all bad

 

Tapered pin that retains the outer control arm bolt

They came out without any drama. I had ordered new main bolts & these, as they typically are a problem. Murphy's Law - if I hadn't bought the new hardware, I would have needed it..

 

Damper on diff mount/control arm forward bracket had stripped bolts

The diff mount is an absolute PITA to remove - the retaining bolt heads cannot be accessed with a socket - the lower half of the mount interferes. They also don't thread into the casing -there are 17mm head nuts that have to be counter held.

had to re-tap to M10x1.5 , to avoid replacing the captive nuts or helicoils

exhaust - still has the original shielding

Shield over rear bumper shock

original forward rear muffler hanger

cut just behind cat

Floors

Poorly installed fuel feed hose - pretty heavy kink

Limiter strap over top of diff snout

Hopefully get more done on it tomorrow

Edited July 6, 2023 by HusseinHolland

[Racer X]

Interesting how the original exhaust and shielding is still intact.

[HusseinHolland]

10 minutes ago, Racer X said:

Interesting how the original exhaust and shielding is still intact.

Yes! They (whomever the PO used to take it to in CA)  cut it to replace the cat, and the rear muffler, but kept all the original hardware & mount straps, which is kinda cool to have.

[EuroDat]

3 hours ago, HusseinHolland said:

Damper on diff mount/control arm forward bracket had stripped bolts

exhaust - still has the original shielding

Poorly installed fuel feed hose - pretty heavy kink

The diff damper looks home made, but it is an original add on to reduce diff vibrations. Some people remove them thinking it is some kind of home made add on.

Interesting photo. The cat has some kind of O2 sensor and an EGR take off. Do you know what is does or where the cable and piping go? The J-tronic didn't have O2 monitoring.

The fuel hose is not suitable for EFI. Most stores try to sell you regular fuel hose, but these cars need high pressure fuel hose with a rating of 4 bar. The EFI runs at 2,5 bar, but the pump can deliver 4 bar.

The floors look in great condition. You will know more when you clean it back to bare metal.

I'm also a little amazed that the original exhaust shielding is still intact. Long time since I saw one with the shielding in such good condition.

[Yarb]

Since you’re doing a complete rebuild/upgrade it might be easier to drop the entire rear assembly and disassemble on the ground.

[HusseinHolland]

6 hours ago, EuroDat said:

The diff damper looks home made, but it is an original add on to reduce diff vibrations. Some people remove them thinking it is some kind of home made add on.

Interesting photo. The cat has some kind of O2 sensor and an EGR take off. Do you know what is does or where the cable and piping go? The J-tronic didn't have O2 monitoring.

The fuel hose is not suitable for EFI. Most stores try to sell you regular fuel hose, but these cars need high pressure fuel hose with a rating of 4 bar. The EFI runs at 2,5 bar, but the pump can deliver 4 bar.

The floors look in great condition. You will know more when you clean it back to bare metal.

I'm also a little amazed that the original exhaust shielding is still intact. Long time since I saw one with the shielding in such good condition.

That all just the (cat-related) floor temp monitoring system that CA models had - there are two warning indicators in the center console, one for cat temp & one for floor temp (monitor is above rear muffler in cargo floor)

Yeah, all that fuel hose mess is going away. I have an assortment of Volvo fuel hose with the proper rating, I may also convert to quick release & nitrile lines in preparation for the VQ35DE conversion.

I'm not going to strip the floors now, just cleanup any loose material & spray fresh 3M Rocker Schutz & undercoat in exposed areas.

I'm vacillating on what to do with the exhaust - I may just make a new 2.5" rear section with new muffler that will be detachable ahead of the subframe. That way, when I do the VQ35DE, I can tie into that instead of having to make the entire exhaust from scratch. I don't think I want to go to 3" on the exhaust.

I have no use for all that shielding once I replace the exhaust, but I'm still going to clean it up.

 

52 minutes ago, Yarb said:

Since you’re doing a complete rebuild/upgrade it might be easier to drop the entire rear assembly and disassemble on the ground.

I think for now I'm just going to do the bushings in place - the axle conversion I'll going to put off as I don't want the car to be down for very long, and getting the companion flanges machined to be concentric for attaching the adaptor flanges is a variable I can't control, time-wise. I need this to be roadworthy so I can take the Volvo pickup off the road to get moving on the V8 conversion. So, just bushings, struts & brakes for now. After that, I still need to make the AC work if I'm going to drive this for the summer & fall.

Edited July 6, 2023 by HusseinHolland

[Yarb]

If you’re changing the struts also,Do your self a favor. Drop the assembly on a trans scissor jack from HF and go from there. I did it the hard way piece by piece.

[HusseinHolland]

Did the mustache bar bushings and the inner control arm bushings. If I can't extract the outer c/arm bushings in-situ tomorrow, I'll have to drop the arms entirely. I'll get the trans jack if that happens, I'll need it anyway for the V8/4l60E drivetrain. Forward bushings are longer than the rears.

For mustache bar, the original bushing sleeves need to be kept, so I holesawed the rubber out & wire brushed the sleeve of residual rubber

rear bushing sleeves came off with just a little soaking

old remnants

[grannyknot]

V8? I must have missed that, which V8 are you thinking about?

[HusseinHolland]

11 minutes ago, grannyknot said:

V8? I must have missed that, which V8 are you thinking about?

The Chevy V8 (LR4) & 4l60e trans are going in the Volvo wagon I made into a pickup truck last year. I just need the Z safe to drive for now.

 

[HusseinHolland]

Dropped the struts/hubs after work, no drama. All drum brake parts removed. I don't want to hack up the back plates, so I'm going to pull the spindles.

This Volvo tool (999-2846)  intended for old RWD prop shafts fit the Z U-Joint

Hopefully I'll have the hubs apart tomorrow, and replace the strut inserts and coil springs

 

 

 

Edited July 7, 2023 by HusseinHolland

[Zed Head]

It's a good time to grease the u-joints on your half shafts.  There are small slotted plugs in the Zerk fitting holes.