240 91 Open Diff to 93 LSD swap

My deadline to finish the "91 245 was Christmas. Delving into the rear axle has f-up'd my schedule. But everything takes me 2 to 3x as long as it should anyway.


I've read the threads on the rear drive swaps...but too many off them were read after I ripped it all apart.


Two questions:
1) I believe this swap is fine without changing the pinion? Its a 1991 245 open Diff wagon getting a 1993 244 (Seden) LSD? Just swap them right? I already made the mistake of having no idea how deep the pinion nut was.

2) As you'll see the second photo, the pinion seal was a PITA to get out. The PO had red thread locker or something on the seal where it mates to the inner pinion shaft. That is totally unnecessary correct?

I also welcome any other advice or comments, before I put it back together.

Ring and pinions are made as a matched set. Even if they're the same ratio they must be changed as a set. That means you need to swap the open carrier ring gear over to the LSD carrier. You should also swap the shims under the carrier bearings over to the LSD carrier making sure they go back on the same side, check the gear contact pattern with marking compound and backlash with a dial indicator.

The pinion seal shouldn't need any additional sealant or glue between it and the housing. The seal should have a bead of sealer on the back to seal it to the housing.

Nice score on Dana Pow-R-Lok.

I would probably put NEW side bearings on that diff. Make sure to note the location of the shims underneath the bearings.

I know it's not a good practice to mix and match pinions and ring gears, but really, in the factory they have a bin for of pinion gears, and someone installs those on the axle. Then someone pulls a ring gear out of a bin and puts it on the carrier. Then someone spends a bit of time shimming stuff around to get them to fit properly. So the shimming is specific to the parts (the clearances needed are not practical for industrially machined parts).

And on to my anecdote - it's a sample size of 1, and it's certainly not 'best practice' at all. But when I put a G80 in my '93 240 - I *totally* shade treed it. They were both 3.73 gearing. So I just paid attention to the lash/slack feel of the currently installed open diff, and then I just swapped the diff itself. Did not touch the pinion *at all*. Did not swap ring gears, left the G80's 3.73 gear on it. I just slid the open diff out, slid the G80 in. And then by feel, noted that the lash/slack felt pretty much identical to the open diff. Seemed good. So I stuck the diff cover on, put fluid in it, and I've been using it like that for about.. 15 years? 35K miles? Most of the time with roughly 300 - 350 whp from a redblck, and the last couple of years with maybe 500 - 550 whp from a turbo LS. I really didn't expect it to survive that (I have a Ford 8.8 I need to swap in at some point), but it's still hanging together, doesn't make any bad noises, seems as fine as can be.

JohnMc said:

I know it's not a good practice to mix and match pinions and ring gears, but really, in the factory they have a bin for of pinion gears, and someone installs those on the axle. Then someone pulls a ring gear out of a bin and puts it on the carrier. Then someone spends a bit of time shimming stuff around to get them to fit properly. So the shimming is specific to the parts (the clearances needed are not practical for industrially machined parts).

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If that were true they would sell ring gears and pinion gears independently. In reality they are always made as a set. Look closely and you will see a hand engraved set of numbers that match on both the ring & pinion in case they get separated. You can see them in this illustration.




Manufacturing tolerances have gotten a lot better over the years. That said, you got really lucky that your mismatched gears aren't noisy.

Thanks guys. I will likely change the bearings before putting the LSD (So that is a G80?) in. I've got the seal out, the pumpkin cleaned out, and the axle painted now. I have the pinion and whole axle that the LSD was in, maybe I should have just swap the whole axles but I think I'm too far now. I haven't the foggiest how to get the pinion out. I thought it would just slip out after the nut and seal were removed. It seems to be in there good. I've got more research to do.



I don't have to worry about too much torque though, its a N/A stock with no plans for any real engine performance mods.



I've only gotten this far thanks to Art Benstein's meticulous and informative picture tutorials.

Not a Dana 30 but a good guide of a diff rebuild.

I see your tone ring count is going to be incorrect, unless you've changed speedometers. Are you aware of that?

Ring and pinions are matched sets, since they gear sets go through a "run-in" on a special machine with a lapping compound.

Advice: Just swap the center sections, and keep the ring and pinions in their respective diffs.

If you're going to remove the pinion to replace the seal or whatever, you'll have to drive it out (put the nut on and hit that, not the pinion threads!). The front/outer pinion bearing is a press fit 99.9% of the time.

Some seals have a locking compound on the outside of them. Yes, they can be a real pain. If you remove the pinion (as mentioned above), you can punch out the seal with a long-ish drift or a long screw driver and hammer.

You can download the entire Dana-Spicer d30 rebuilt and repair manual for free. Plenty of PDF versions floating around. Read it, understand it, you'll be fine.

shoestring said:

I see your tone ring count is going to be incorrect, unless you've changed speedometers. Are you aware of that?

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No I don't even know what a ring count is? I'm assuming it has to do with the speed sensor? I still have the axle that the LSD was in, so I'll check that out.



In the picture is there a missing bolt on the LSD or is that hole not supposed to have a bolt?

Yelp I had a buddy that claimed he could swap just the pinion gear in his dif. Well he made it about 5 miles then called me to come pull him home in my volvo. Dont try it, he destroy his dif and had to buy a whole rearend. Now I thought it would of made it farther than five miles, but. Anyways find you a local that can help you with the swap. If not read and listen. Good luck

RickATL said:

No I don't even know what a ring count is? I'm assuming it has to do with the speed sensor? I still have the axle that the LSD was in, so I'll check that out.

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The sensor wheel on your LSD is for ABS cars. You need to cut out the bars so you have 12 evenly spaced like the one in this pic or buy a new sensor wheel to keep your speedo accurate.

RickATL said:

In the picture is there a missing bolt on the LSD or is that hole not supposed to have a bolt?

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No, there's definitely supposed to be a bolt in there. It's unusual that it would be missing from an assembled rear end as there isn't enough room for the bolt to come out. Hopefully someone hasn't been there before you and stripped the threads because they're probably left hand thread. Get the new bolt from Volvo even though it's expensive.

https://www.tascaparts.com/oem-parts/volvo-screw-1377049

FYI, it's a Dana Pow-R-Lok, not a G80.

hiperfauto said:

The sensor wheel on your LSD is for ABS cars. You need to cut out the bars so you have 12 evenly spaced like the one in this pic or buy a new sensor wheel to keep your speedo accurate.

No, there's definitely supposed to be a bolt in there. It's unusual that it would be missing from an assembled rear end as there isn't enough room for the bolt to come out. Hopefully someone hasn't been there before you and stripped the threads because they're probably left hand thread. Get the new bolt from Volvo even though it's expensive.

https://www.tascaparts.com/oem-parts/volvo-screw-1377049

FYI, it's a Dana Pow-R-Lok, not a G80.

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O.k.thanks thats really helpful. I likely took that bolt out myself. (It was 3 or 4 years ago.) I was learning by disassembly.



So im guessing ill find the Dana pow-r-lok in the dana 30 manual or does it have different documemtation.

The greenbook has information about the LSD.

Enter 4_46 TP30039-2_rear_axle_repairs into the search box to download the greenbook.

https://ozvolvo.org/archive/

You've found the best LSD available stock for a Volvo rear end. Even better than a Truetrac etc. Congratulation. Check the diameter of the tone ring. IIRC it's not the same. The sensor if the older differential, cover made if steel, us hard to find nowadays in Germany. And never swap not matched ring gears. You may have luck.
You will get a noisy one
Worst case is: you will destroy the rear end.

If you would know how to work properly on a rear end you will be able to save it from being destroyed...
Take yourself a favour and ask someone with real knowledge to give a help.

The other solution with tone ring us to swap the instrument or add a signal reducer. Made to adjust the Speedo. Good luck, Kay