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Official differential information.

BTW, Greg is a modest guy.. Doesn't like to blow his own horn. His best time was a 124 second run up the hill. People work on it for years to join the sub 2 minute club. This was his first time. Awesome run. What was it Greg, 6th fastest out of 56 entries? In a Volvo no less. :)
 
2manyturbos said:
BTW, Greg is a modest guy.. Doesn't like to blow his own horn. His best time was a 124 second run up the hill. People work on it for years to join the sub 2 minute club. This was his first time. Awesome run. What was it Greg, 6th fastest out of 56 entries? In a Volvo no less. :)
Click to expand...

nice. highfives.

I'm going to update the main post in a bit, to summarize the "findings" here. still disappointing we don't have an official differential breakdown.

Sim
 
basic
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involved
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Thanks for posting up those videos! Those are great.

Thanks Roy! I am glad I made it up there this year. Lets see how fast you can drive it next year
 
I've been doing my digging in this area and I'm still not 100% clear on one thing? What exactly do we have in these things? When I look on Summit, I'm under the impression that I should be looking for Dana 30 27 spline stuff to replace my open diff with. Is this correct?

And is the G80 a 27 spline too?

Sorry.... :oops:
 
BDKR said:
I've been doing my digging in this area and I'm still not 100% clear on one thing? What exactly do we have in these things? When I look on Summit, I'm under the impression that I should be looking for Dana 30 27 spline stuff to replace my open diff with. Is this correct?

And is the G80 a 27 spline too?

Sorry.... :oops:
Click to expand...

I don't have answers for you, but I'm sure we can dig up something. I'm coming to the slow conclusion that the average t-bricker doesn't know a whole lot about diffs (save for some elite t-brickers). maybe it's because they are more simple than engines? maybe they're not the focus? I don't know; I think it's fair to ask a lot of questions "we think are stupid" in this thread, because I'm sure a lot of us are wondering (and don't know). plus, that's not a stupid question - no apology necessary.

love the vids. I watched the first one, and was like, "yeeeah - still don't get it; this is all a "black box" to me...", and then about half-way through the second one I was like, "HOLY SHAT THAT IS A FABULOUS IDEA!!" genius.

Sim
 
simey_binker said:
I don't have answers for you, but I'm sure we can dig up something. I'm coming to the slow conclusion that the average t-bricker doesn't know a whole lot about diffs (save for some elite t-brickers). maybe it's because they are more simple than engines? maybe they're not the focus? I don't know; I think it's fair to ask a lot of questions "we think are stupid" in this thread, because I'm sure a lot of us are wondering (and don't know). plus, that's not a stupid question - no apology necessary.

love the vids. I watched the first one, and was like, "yeeeah - still don't get it; this is all a "black box" to me...", and then about half-way through the second one I was like, "HOLY SHAT THAT IS A FABULOUS IDEA!!" genius.

Sim
Click to expand...

I swear there is some strange TB voodoo jumping off. Never fails, but I can search and search and search fruitlessly, then ask a question on TB, then stumble upon the answer after I've posted the question.

http://www.davebarton.com/volvorearends.html

:rofl:
 
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2manyturbos said:
Kildea,

Take a look at the pictures. It looks to me like what actually locks the 2 axles together are the splines on 2 of the disc shaped parts. That is what is meant by locker. Mechanically locked together. A clutch type limited slip actually uses clutch discs just like in an automatic trans clutch pack to drive the axles at the same speed. When the clutch discs wear, no more limited slip. I have never taken a G80 apart, however, it looks like the rest of the Eaton lockers to me. Pure mechanical interlock. So, with the locker in the pictures, what do the clutches do? Do they actually drive the axles, or do they cause mating collars to move relative to each other causing them to lock toghther, just like in a manual transmission?
Click to expand...

Uhh...
No.
The 1041(G80) has clutches, too.
There are torque differential lockers, and speed differential lockers.
The 1041 is a speed locker.
 
simey_binker said:
I don't have answers for you, but I'm sure we can dig up something. I'm coming to the slow conclusion that the average t-bricker doesn't know a whole lot about diffs (save for some elite t-brickers). maybe it's because they are more simple than engines? maybe they're not the focus? I don't know; I think it's fair to ask a lot of questions "we think are stupid" in this thread, because I'm sure a lot of us are wondering (and don't know). plus, that's not a stupid question - no apology necessary.
Sim
Click to expand...


They aren't the focus IMO. The torsen diff is pretty well documented, as is the G80.

If you aren't satisfied with that, I would dump it and go with a different diff. There is no magic bullet with these.

I hate the G80 personally because with the ones i have driven at least I notice it lock and unlock as I get on/off the throttle and it drives me insane.

The torsen style tru-tack that most people buy is ok.

I just don't like them because if you actually unload the inside tire, there is no torque really driving the worms gears so you have basically castrated it (it is basically open except for the bit of preload).

I personally need a clutch type- and unfortunately the only 2 options are the extremely ****ty dana trac-lok and the very good but basically unabtainable ZF.

A D30 with upgraded axles and a ZF clutch type would be a really nice diff...


This is why the car has an 8.8 under it now. This was an easy swap for the difference of 25lb which will go away with the bolt-on aluminum calipers/2 peice rotors that they basically give away when you have something with Ford written on it. YMMV.:cool:
 
Official Differential Information

I have found more info:

1992 Volvo Tech & Spec dated: September 25, 1991
ABS Brakes: Anti-lock brakes will be standard equipment on all 1992 Volvos sold in the United States.
Automatic Locking Differential: The automatic locking differental is standard on all 740, 940, and 960 Volvos.

1993 Volvo Tech & Spec dated: September 11, 1992
ABS Brakes: Anti-lock braking system is again standard equipment on all new Volvo models sold in the U.S.
Automatic locking differential:
940: Both sedans and wagons are equiped with an automatic locking differential.
960: Both sedans and wagons are equiped with an automatic locking differential.

1994 Volvo Tech & Spec dated March 15, 1994
ABS Brakes: Anti-lock braking system is again standard equipment on all new Volvo models sold in the U.S.
Automatic locking differential: All new 940 series Volvos sold in the U.S. for 1994 will be equiped with an automatic locking differential as standard equipment. All 960 sedans & wagons have an automatic locking differential.

1995 940 sedans & wagons: ABS & ALD are standard as per 1995 Volvo 940 Features.
1995 960 wagons: ABS & ALD are standard as per 1995 Volvo 960 Features.

I will have the ratios and what is fitted with ABS & ALD later, I don't have it sorted yet.
 
hm - did the G80 come in various other vehicles as well? seems like GM used them (by the look of one of those adverts). and we're saying that we can take the G80 diff (the core, inside the housing), and swap it with my POS open diff? as BDKR asked; are we dealing with the same number of teeth on the splines? do I swap the pinion and ring gear onto the G80 as well?

I'm starting to get the terminology for the different rear ends too... sounds like I've got a Dana 31 aka M31 aka 1031. I think I'm liking the G80 setup... although I'm sure there'll be a lot of benchmarking of all the different diffs in here. the 1030 was in some early 240s, and the 1041 has the G80 (as stated by peehound up there).

so we're saying, find myself a G80 diff, cut 2 of every 3 teeth on the tone ring gear, and chop the flywheel weight off. then remove my rear wheels, remove backside of diff housing, loosen axles, slide them out, take out my open diff, chop a cm off the passenger-side axle, and plug in the G80. swap the ring gear if necessary....

I think this is slowly coming together...

Sim

thanks,
Sim
 
2manyturbos said:
Kildea,

Take a look at the pictures. It looks to me like what actually locks the 2 axles together are the splines on 2 of the disc shaped parts. That is what is meant by locker. Mechanically locked together. A clutch type limited slip actually uses clutch discs just like in an automatic trans clutch pack to drive the axles at the same speed. When the clutch discs wear, no more limited slip. I have never taken a G80 apart, however, it looks like the rest of the Eaton lockers to me. Pure mechanical interlock. So, with the locker in the pictures, what do the clutches do? Do they actually drive the axles, or do they cause mating collars to move relative to each other causing them to lock toghther, just like in a manual transmission?
Click to expand...



no there is no mechanical lock, the two pieces are ramps they ramp against one another and compress the two wet clutchpacks in the photos.

the splines you mentioned above connect the spider gear to half of the clutches, you'll notice the mating splines on the inside diameter of the clutch pack in the photo, the outside ears on the other half of the clutch discs are mounted to the housing, so as the clutch discs are compressed it locks the housing to the spider gear, while they are not compressed the spider gear is free to turn independent of the housing.

there is no mechanical locking in this differential, i took it apart, modified it and reassembled it, if you do the same you will see that the clutchpacks are what causes the locking.

Pure mechanical interlock
Click to expand...

take one apart or look again at the photos this is just false, sorry :)

if you read my follow-up post you will understand the process, the flyweights lock the ramp with respect to the housing, this causes the ramps to slide relative to one another and as i said above compress the clutchpacks, without the compression the ramps would just keep bumping over each other and it would never "lock"
 
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simey_binker said:
yeah - I think it's clear how it works, with those videos.

Sim
Click to expand...



**** i din't see those before, that's pretty cool ...

another option is the ez-locker style, which replaces the spider gears in your current setup, it's a mechanical type and somewhat more noisy ... but they are cheap and easy to install ... just an idea:

something like this:
http://cgi.ebay.com/ebaymotors/Jeep...007QQitemZ170239153328QQrdZ1QQsspagenameZWDVW


also you need one for a dana 30 ... the gm pumpkin will not fit.
 
i always thought it was a dana 30, that's what i have.
the 1031 is the volvo axle casing type, shared by several years in 240 and 740 for sure.
the 1031 houses a dana 30 diff.
 
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