Rear end rebuild

[Knockwurst]

It's been a while since I've been on here! You may remember that following a head gasket failure last year, I took the opportunity to rebuild the full engine and suspension over the winter, as well as strip the old under seal back to metal and repainted in body colour. Well, today it's time for the rear end to get the same treatment.

I put the hardtop on to make more room in the garage and dropped the rear diff and suspension together. Looks like it's never been off before. The diff carrier mounting hole is corroded, so I'll need a new one (if anyone has a good second hand one that they are prepared to sell, please let me know). The underbody seems OK in general. I was really lucky at the front as no welding was required, but the rear needs quite a few localised repairs.

The condition off all bushes was shocking. The main mounting bushes had separated from the housing. The diff bushes were perished and partially disintegrated and the trailing arm bushes are also badly worn. All this would explain why it has very vague handling and tends to wander around. Also suffered from pronounced twitch.

Some pictures of the progress image.jpgimage.jpg

[DJT]

At least you'll have a nice tight back end when you've finished......

[tractorjames]

At least you'll have a nice tight back end when you've finished......

Nothing worse than a loose back end.

[Knockwurst]

So I've assessed what I think I need to do. Apart from the duff bushes affecting handling, there was nothing noticeably wrong from the driveline or rear suspension whilst driving, so I don't think I need to do anything major. My plan is:

- new UJs for the prop and drive shafts
- new oil seals for the diff nose and driveshaft input
- replace diff cover gasket
- add strengthening ribs to diff nose carrier and replace quill shaft bearing
- new poly bushes all round
- replace corroded diff mounting and powdercoat all components
- new springs and shocks
- all new bolts and fixings
- renew handbrake cable and Flexi hoses

Any advice welcome. Are there any other jobs which I should do around the diff or driveshafts?

Thanks, Simon

[new to this]

So I've assessed what I think I need to do. Apart from the duff bushes affecting handling, there was nothing noticeably wrong from the driveline or rear suspension whilst driving, so I don't think I need to do anything major. My plan is:

- new UJs for the prop and drive shafts
- new oil seals for the diff nose and driveshaft input
- replace diff cover gasket
- add strengthening ribs to diff nose carrier and replace quill shaft bearing
- new poly bushes all round
- replace corroded diff mounting and powdercoat all components
- new springs and shocks
- all new bolts and fixings
- renew handbrake cable and Flexi hoses

Any advice welcome. Are there any other jobs which I should do around the diff or driveshafts?

Thanks, Simon

Simon

sounds like your going to be busybut if your going that far,how about changing the trailing arm threads,from NUF to NUC,another mod would be weld tubes in the holes at the ends of the rear subframe arms as the hole can go elongated

good luck with repairs

dave

[mole42]

I hope you have better luck that I with the driveshaft oil seals - I still haven't manages to get the flanges off!

While you're doing the driveshaft oil seals, why not replace the bearings as well?

[Knockwurst]

Thanks for the suggestions. The 6 small trailing arm to hub studs all look in great shape, so I think I'll leave alone. I have stripped a large amount of the old paint and under seal and body mastic off today. There is some welding to do around the rear of the sill, on the chassis leg where the suspension spring sits and a couple of other really small repairs. Overall I'm happy with the condition, it is really solid, apart from the areas mentioned.

I don't have the circlip type UJs. What is involved in changing the other type, it doesn't look easy! There doesn't appear to be any play in them anyway, so I may leave alone if it too difficult to swap them.

[new to this]

Thanks for the suggestions. The 6 small trailing arm to hub studs all look in great shape, so I think I'll leave alone. I have stripped a large amount of the old paint and under seal and body mastic off today. There is some welding to do around the rear of the sill, on the chassis leg where the suspension spring sits and a couple of other really small repairs. Overall I'm happy with the condition, it is really solid, apart from the areas mentioned.

I don't have the circlip type UJs. What is involved in changing the other type, it doesn't look easy! There doesn't appear to be any play in them anyway, so I may leave alone if it too difficult to swap them.

I don't think you can modify the older type of drive shafts to cir-clip ,i think you just have to look out for a set of drive shafts with cir-clips then there a straight swap over, that's what im going to do

dave

[PhilB]

I have staked UJ's driveshafts. One started squeeking and then recently knocking so I took it out.
Took it to NW Propshafts and they took out both old UJ's in the driveshaft as told me both knackered, and replaced with new UJ's - £80 + VAT = £96
(They supplied the replacement UJ's in that)
Put it back in last week and running silent and happy again.
So suggest you find a propshaft specialist local to you and get a quote
Good Luck Phil

[simonmetalback]

Hi Simon

Another Simon with the same task here, unfortunately my diff extension sheared so thought I would drop the whole lot and do the same as you. I was going to fit the BMW diff and do the Monarchs upgrade. I even gone as far to purchase a BMW diff, but the penny's are short in the Waller house old as new Kitchen and holiday stopped that plan. ( will do in the future) car has been off the road now for six weeks and I'm gutted. So I'm just going to weld the housing up and do the same as you. Any tips would be great, I plan to drop mine down with the help of my brother at half term.Im only in Bicester so if you need a hand with anything give us a shout. Hope the rebuild goes ok.

[Knockwurst]

Hi Simon

Another Simon with the same task here, unfortunately my diff extension sheared so thought I would drop the whole lot and do the same as you. I was going to fit the BMW diff and do the Monarchs upgrade. I even gone as far to purchase a BMW diff, but the penny's are short in the Waller house old as new Kitchen and holiday stopped that plan. ( will do in the future) car has been off the road now for six weeks and I'm gutted. So I'm just going to weld the housing up and do the same as you. Any tips would be great, I plan to drop mine down with the help of my brother at half term.Im only in Bicester so if you need a hand with anything give us a shout. Hope the rebuild goes ok.

Cheers Simon, thanks for the offer. Dropping the whole subframe was straight forward, the hardest bit was getting the car high enough to allow enough room to slide the subframe and a trolley jack out together. I'll keep this thread running with things I find. First job is sorting the underbody. I have all the old underseal off the LH wheel arch, back to body colour. I have a few small repairs around the spring mount, but the rest looks really solid, just a quick sand back, then etch prime ready for body colour stonechip. There is a fair amount of surface rust underneath, but nothing that needs cutting out, so it will be cleaned up, rust killer, zinc prime, then stonechip. The studs that hold the diff mount on are badly corroded and won't shift, so I may need to cut them out. Foolishly, I put the hardtop on, now I can't get to the topside of the stud to replace (I'm actually wondering whether they are on the boot side, as I don't recall seeing them in the hood stowage area when I undid the top of the shocks)!

My blast cabinet looks too small for the training arms and subframe arms , so I may just pay to get them blasted and powder coated. There is a place local to me that I can use.

[new to this]

Cheers Simon, thanks for the offer. Dropping the whole subframe was straight forward, the hardest bit was getting the car high enough to allow enough room to slide the subframe and a trolley jack out together. I'll keep this thread running with things I find. First job is sorting the underbody. I have all the old underseal off the LH wheel arch, back to body colour. I have a few small repairs around the spring mount, but the rest looks really solid, just a quick sand back, then etch prime ready for body colour stonechip. There is a fair amount of surface rust underneath, but nothing that needs cutting out, so it will be cleaned up, rust killer, zinc prime, then stonechip. The studs that hold the diff mount on are badly corroded and won't shift, so I may need to cut them out. Foolishly, I put the hardtop on, now I can't get to the topside of the stud to replace (I'm actually wondering whether they are on the boot side, as I don't recall seeing them in the hood stowage area when I undid the top of the shocks)!

My blast cabinet looks too small for the training arms and subframe arms , so I may just pay to get them blasted and powder coated. There is a place local to me that I can use.

Knockwurst

the diff pins heads, are inside the rear seat pan,you have to cut an access panel in the seat pan,to get to the top of the pins,look through Edds project he has pictures that may help you better

dave

[Knockwurst]

Knockwurst

the diff pins heads, are inside the rear seat pan,you have to cut an access panel in the seat pan,to get to the top of the pins,look through Edds project he has pictures that may help you better

dave

Cheers Dave

[Knockwurst]

image.jpgimage.jpg

Some more progress. On the last MOT I had an advisory for a small hole above the nearside spring hanger, so I've cut out the rot and welded in new metal- as you can see, it was a bit more than a small hole, but I think this is the worst part that I need to tackle on this rebuild. I have a new spring hanger cup that I am welding on today. The old one was spot welded to the chassis leg, should I drill and plug weld or seam weld the hanger on?

[Ian F]

Dave/Knockwurst

You can change staked UJ's to circlip type as I had it done some years ago with my Stag. I was fitting new Rislan coated driveshafts ( which were circlip type) and found that my hubs were staked. To be fair, I was also replacing the hub bearings, so once stripped, the lot went to Proptech in Hartlebury, Kidderminster and they machined the necessary diameter and circlip groove. That was about 6 years ago and (touch wood) no trouble since. They also fitted grease nipples to the UJ's!

Ian