25 replies to this topic

[jonboyb]

Just trying to determine the differences.  My 84 has the LSD but it's a bit noisy and I fear may be on the way out.  Not the normal moan during turns but a "vibratory" sound over 60 mph.  You don't feel any vibration...just the sound is like a harmonic from vibration.  Also tends to spin one side only on occasion and I know the previous owner had it rebuilt by someone like Maaco so I don't have alot of faith.  Going to put fresh fluid and LSD additive in to see if it helps.  Anyways, know very little about pumkin dimensions flatty vs. widebody and axle/torque tube spline differences but are there any interchagable parts?  Have tons of 87-89 rear LSD's from widebodies and it would be awesome if I might be able to rebuild my flatty LSD using a donor widebody diff (and no.....I'm not doing a 5-lug swap ).  

I have access to 3 real flatty LSD's but all 3 cars are plenty restorable and I don't want to start parting good cars.

Edited by jonboyb, 05 October 2010 - 01:38 PM.

[Dred_85.5_TSI]

the lsd diffs should be the same up to 87, 88&89 I'm not so sure about. but I think as long as it is a lsd running four bolt shafts it should be O.K.

[StarquestRescue]

The non intercooled cars used a 7.25 ring and pinion. The intercooled cars used a 8" and a different lsd setup. Not much looks to interchange pre the parts manuals. The non intercooled 4 bolt axles are longer and thinner than the intercooled 4 bolt axles.

Many have used the intercooled 85.5-87 lsd in the none intercooled cars with the non intercooled axels without any apparent problems. The hub flange is slightly different between the non and intercooled 4 bolt axels.

The front diff of 4 cly 4wd trucks used the 7.25 ring and pinion as well. Most were 3.90 i think. Some 4.22

Edited by StarquestRescue, 10 August 2012 - 09:15 PM.

[FlattopMike]

Torque tube and differential from the donor, your axles.

[MikeMeyerhoff]

FlattopMike, on 05 October 2010 - 04:15 PM, said:

Torque tube and differential from the donor, your axles.

Yep to what everyone has said:  stay pre-88.  The axle flanges are different from non-ic to ic.  Just enough that they won't work.  The spline count is the same so they are interchangable on that end.

Torque tubes stay with the differential due to length differences.

Edited by MikeMeyerhoff, 05 October 2010 - 06:14 PM.

[Komeuppance]

StarquestRescue, on 05 October 2010 - 04:13 PM, said:

The non intercooled cars used a 7.25 ring and pinion. The intercooled cars used a 8" and a different lsd setup. Not much looks to interchange pre the parts manuals. The non intercooled 4 bolt axles are longer and thinner than the intercooled 4 bolt axles.

Many have used the intercooled 85.5-87 lsd in the none intercooled cars with the non intercooled axels without any apparent problems. The hub flange is slightly different between the non and intercooled 4 bolt axels.

The cly 4wd trucks used the 7.25 ring and pinion as well. Most were 3.90 i think.

Are you saying that 85.5-87 IC'd cars are an 8"??  I was pretty sure that the 8" was the 88/89.

-Robert

[StarquestRescue]

Komeuppance, on 05 October 2010 - 09:22 PM, said:

Are you saying that 85.5-87 IC'd cars are an 8"??  I was pretty sure that the 8" was the 88/89.

-Robert

Yes, all the intercooled usa cars got the 8" rears. The difference in the 88-89 is in the side gears and differential case to accommodate the bigger 88-89 axles. I have not been inside anything 7.25, but do have the microfiche and some old manuals.

[louswheel]

So, I 've got this 85.5 intercooled flatty, can I use the axles from that sucker for my '87?  I've got 5 rear ends at my house, I'm gonna take a loot at them, I've got two 88's one auto, one 5 speed, I've got one '87 and one 85.5 and some other odd one that does not look like the others which I take is probably a non intercooled.

[Metric-man]

The Australian's and their flatsiders never were offered the LSD option they swap the pre 88/89 LSD Diffs when ever they can get one.

There are about five types of Diffs offered for the Starquest and louswheel01 might have them all

(louswheel01 when are you going to get a digital camera besides your Phone ?)

later when I get a chance I'll look up part numbers for the different years so you can match them..

be nice to have a picture or two of the real thing hint, hint ..

[psu_Crash]

MikeMeyerhoff, on 05 October 2010 - 06:12 PM, said:

The axle flanges are different from non-ic to ic.  Just enough that they won't work.  

I found that out the hard way after going rounds with Autozone about why the axles they sold me didn't fit but were supposedly the "right" ones    
I just drilled out the flange holes on the axles a little and bolted them in. So far so good

[Tim_C.]

jonboyb, on 05 October 2010 - 01:37 PM, said:

Just trying to determine the differences.  My 84 has the LSD but it's a bit noisy and I fear may be on the way out.  Not the normal moan during turns but a "vibratory" sound over 60 mph.  You don't feel any vibration...just the sound is like a harmonic from vibration.  Also tends to spin one side only on occasion and I know the previous owner had it rebuilt by someone like Maaco so I don't have alot of faith.  Going to put fresh fluid and LSD additive in to see if it helps.  Anyways, know very little about pumkin dimensions flatty vs. widebody and axle/torque tube spline differences but are there any interchagable parts?  Have tons of 87-89 rear LSD's from widebodies and it would be awesome if I might be able to rebuild my flatty LSD using a donor widebody diff (and no.....I'm not doing a 5-lug swap ).  

I have access to 3 real flatty LSD's but all 3 cars are plenty restorable and I don't want to start parting good cars.

You are the same as me but worse! I wouldn't switch to 5 lug either on a flat body. The 4 lug is lighter and more nimble to drive. The handling of the car seems more precise on my flatties. I guess it is the light weight more so, but I wouldn't want to change anything on the 3 running flatties I have unless I want to experiment, which I plan to do on one.

I am holding a car without taking parts from it too. I hope to someday put it back on the road, or sell it to some one who will. The engine runs fine, but it needs springs and struts all the way around, and all steering components replaced, including the gearbox, coupler, ps pump and lines.

As for the rear end, I plan to swap in an intercooled '87 rear and TT into my '83 daily driver for better snow traction. I'll be sure to post about it. I might lose a little of the precision handling since the '83 is non LSD and very light. It is hard to explain properly, but the flatties rear seems to follow the front easier for better mileage. My widebodies stick to the pavement better for performance handling, but the flatties are nicer for every day driving around town.

[Coke]

So let me get this straight.

I have an '86 NON-Intercooled car.

I want to upgrade to LSD.

I use an 87 and older LSD pumpkin+torque tube

....but....

I must use NON-LSD axle shafts?

Edited by Coke, 18 October 2010 - 01:17 PM.

[MikeMeyerhoff]

Coke, on 18 October 2010 - 01:17 PM, said:

So let me get this straight.

Too easy.  

And yes, you've got it exactly right.   If you really want to use the LSD axle shafts, you have to swap hub flanges.

[Tim_C.]

Coke, on 18 October 2010 - 01:17 PM, said:

So let me get this straight.

I have an '86 NON-Intercooled car.

I want to upgrade to LSD.

I use an 87 and older LSD pumpkin+torque tube

....but....

I must use NON-LSD axle shafts?

Yes, your original axle shafts will work.

[Komeuppance]

You don't HAVE to use your original non-ic shafts, you can do the same but opposite of this:

psu_Crash, on 07 October 2010 - 10:36 AM, said:

I found that out the hard way after going rounds with Autozone about why the axles they sold me didn't fit but were supposedly the "right" ones    
I just drilled out the flange holes on the axles a little and bolted them in. So far so good

-Robert

Edited by Komeuppance, 28 October 2010 - 04:38 AM.

[Tim_C.]

Komeuppance, on 28 October 2010 - 04:37 AM, said:

You don't HAVE to use your original non-ic shafts, you can do the same but opposite of this:
-Robert

Do you mean drill out the spindles, not the axles?

[Metric-man]

jonboyb, on 05 October 2010 - 01:37 PM, said:

Just trying to determine the differences.  My 84 has the LSD but it's a bit noisy and I fear may be on the way out.  Not the normal moan during

turns but a "vibratory" sound over 60 mph.  You don't feel any vibration...just the sound is like a harmonic from vibration.  Also tends to spin one

side only on occasion and I know the previous owner had it rebuilt by someone like Maaco so I don't have alot of faith.  Going to put fresh fluid

and LSD additive in to see if it helps.  Anyways, know very little about pumkin dimensions flatty vs. widebody and axle/torque tube spline

differences but are there any interchagable parts?  Have tons of 87-89 rear LSD's from widebodies and it would be awesome if I might be able to

rebuild my flatty LSD using a donor widebody diff (and no.....I'm not doing a 5-lug swap ).  

I have access to 3 real flatty LSD's but all 3 cars are plenty restorable and I don't want to start parting good cars.

This is the deal,
there are FOUR differentials they are coded:
(5GO) , (5GO LSD) , (5.1GO) , (6GO LSD)

5GO and 5.1GO are NON-LSD 5.1GO was only offered in the year 86 87 LE model, I believe they were later used for the 3000GT rear 4WD differentials pre 4WS models
(from some of my past research, and I believe there maybe a performance LSD kit that is made by KAZZ for them).

5GO LSD were offered as an OP option in the year 83 84 LS and LE model ,
and all the way up to the first (ONE) month of production of the year 88 ESI June of 1987.

6GO LSD differentials were offered as standard equipment in the year 85.5 first intercooled flatties ,
and up to the ESI models 88/89 model year they are also referred to as the (6GO 8412) because of their introduction in December of 1984.


The internals between the 5GO LSD an 6GO LSD differentials are interchangeable as a whole because of similar carrier (casing) assembly but not the
individual parts such as the gear sets, clutch plates, springs or pinons.

The different differential models probably have a serial number stamped or attached by a metal tag
5GO LSD could possibly have the numbers 33033A and or S84345 , the 6GO LSD could have the numbers 33033AX and or S87489

Identification is easiest for the non LSD models and the smooth rather flat shape of the casing.
The serial number for the 5.1GO may read 34034 and or S86770 the 5GO may simply read just 34034.

[shift1313]

starion_cult, on 08 November 2010 - 04:49 AM, said:

This is the deal,
there are FOUR differentials they are coded:
(5GO) , (5GO LSD) , (5.1GO) , (6GO LSD)

5GO and 5.1GO are NON-LSD 5.1GO was only offered in the year 86 87 LE model, I believe they were later used for the 3000GT rear 4WD differentials pre 4WS models
(from some of my past research, and I believe there maybe a performance LSD kit that is made by KAZZ for them).

5GO LSD were offered as an OP option in the year 83 84 LS and LE model ,
and all the way up to the first (ONE) month of production of the year 88 ESI June of 1987.

6GO LSD differentials were offered as standard equipment in the year 85.5 first intercooled flatties ,
and up to the ESI models 88/89 model year they are also referred to as the (6GO 8412) because of their introduction in December of 1984.


The internals between the 5GO LSD an 6GO LSD differentials are interchangeable as a whole because of similar carrier (casing) assembly but not the
individual parts such as the gear sets, clutch plates, springs or pinons.

The different differential models probably have a serial number stamped or attached by a metal tag
5GO LSD could possibly have the numbers 33033A and or S84345 , the 6GO LSD could have the numbers 33033AX and or S87489

Identification is easiest for the non LSD models and the smooth rather flat shape of the casing.
The serial number for the 5.1GO may read 34034 and or S86770 the 5GO may simply read just 34034.

also 5g0lsd was standard on the ES cars.  If i remember right 84 had a different length TT from other non IC LSD cars.  

also 4lug vs 5lug, i dont see the 4 lug being a weak spot at all.  I dont like the way the 5lug brakes are setup with the deep "hat".  4 lug is a much lighter package:)

[Tim_C.]

shift1313, on 14 November 2010 - 08:05 PM, said:

also 4lug vs 5lug, i dont see the 4 lug being a weak spot at all.  I dont like the way the 5lug brakes are setup with the deep "hat".  4 lug is a much lighter package:)

I agree. The lighter weight doesn't require the heavy duty 5 lug assembly. Even with considerably more power than stock, the 4 lug axles are plenty strong. Ask people who drift the flatties.

[TurboDoorHandles]

I remember being told by so many all us diffs were 8". I'd love for someone to truely confirm an 84 or 83 lsd is actually a 7.5. If so, then that is the lsd to have to fit the fire arrow, or challenger/sapporo/scorpion/lambda  rear end.