Hey guys, I have a 9 bolt as well and was looking through this thread, sounds awesome. My rearend was swap from a bastard 10 bolt off an 85 z28, now its under my 88 that also had a 10 bolt under it, i sold that unit to a car club member. Now to my question, i went to the link posted above for sourcing the diff, but it gave me a description about what it fits, so i clicked a few links to find it and came across 3 diffs. 2 have the m78 in mind with 1 reading "torque lock gm ve commodore" and the other reading "TORQUELOCK FORD FALCON LSD M86 BA TO BF XR6 TURBO IRS AND SOLID AXLE". Of these 2 which is the correct one to grab or do i do better just sending an email about one? Thanks guys sorry for the text.

 

I sent an email and ended up purchasing the TORQUE LOCK M78 28 SPL.

David from supafspares helped a lot.

 

I would just email Dave. He is aware of this mod and several of us have bought from Supa-F. When I contacted them they seemed unaware of the fitment of this diff into a non-Holden application. They understand it works for us now.

GD

 

Question....

So I recently got the Mace Helical diff for my 89 IROC.. The factory setup in the car was a 2.77 ratio. I managed to source a really nice 3.27 B/W factory gear set from a Grand National. Being my original carrier was a "2 series" and my 3.27 gears were from a "3 series" am I screwed? Does anyone make a ring gear spacer for the 7.75" if I need one? I have yet to assemble the diff with the new carrier and gear. I didn't want to press the bearings on the carrier or pinion until I was sure. Anybody know if this setup will work without a spacer on the ring gear?

So after putting the Mace true trac next to my old series 2 carrier it looks like the Mace IS a 3 series, so I think I'm good with the thin 3.27...

Thanks!

 

Grand nationals came with 9 bolts?!?

 

Yeah right? That's what I said... Mostly was in the LE1 and the Turbo Trans Am... Guess they stuffed it in a few others.... BTW, there's a nice set of Borg Warner 3.27's on ebay right now...

https://www.ebay.com/itm/Used-GM-7-7...sAAOSw149gBxNH

GET IT WHILE IT'S HOT!

 

From factory 2.7x to new 3.2x. Will it not increase engine rpm by 4 to 500 in each trans gear pull?

 

Never heard of a 9 bolt in a GN... So I asked my GN friends. No 9bolts. All used the 8.5 10bolt

 

Your right, my bad... They did offer a 3.27 in the GN but it was the 10 bolt 8.5 r/p...

 

so the chances of an 8.2 gearset from a 3 series 10 bolt working with a 9 bolt carrier ,i dont think its gonna work.....get a 3.27 or higher gear-set FOR A 9 BOLT and do the swap,just make sure the gears work with the carrier you have.

 

I keep forgetting to post this when a 9-Bolt Thread is actually active.

Most of you guys have probably used Axle-Seals that are similar/ look similar to these:




These are not a bad seal and they will do the job...
However they are delicate and not made of the most ideal materials.

Instead, I have been using these Axle-Seals from SKF for about the last 20 years, and they work quite well!







These seal have lip-seals facing in both directions to seal against the Axle-Shafts.
In addition, there is sealing material facing outwards to seal against the Axle-Tubes/ Differential Assembly.

These are by far the best performing Axle-Seals that I have ever installed into a 9-Bolt Differential Assembly.

About 11 years ago; I purchase large quantity of these seals, including all of the seals and Inspection-Cover Gasket to keep as surplus.
I can only hope that the quality of these seals has remained.

Have you guys ever picked-up the box that an auto-part is inside of...
Only for the box to have some actual weight to it...
Then think to yourself: "Now that is a quality part".

??? Let me know!

 

This seal is actually incorrect and won't work properly, oil will leak past the outside since there is nothing to seal it to the housing.

It's not that this is the best performing, it is the correct seal, though one is for a specific orientation and the other is a "universal" fit since it doesn't have the directional wipers in the inner seal. 16491 can be used for either side. The problem is that these are getting harder to find and are now quite expensive. Even though I have posted it several times no one is buying the proper seal, then they come to this site and complain. Yukon actually makes/sells these seals still but are very expensive. I was actually able to find one of the seals from another brand that is correct, but it is no longer available.
If you buy the Timken seal that comes up as the "correct number", but completely coated in rubber, it DOES work, it just doesn't fit correctly (as do the ones you posted) and you need to put a spacer between the retainer plate and the axle housing so it doesn't crush the seal. I am using one Timken seal in my car now and it doesn't leak

 

Interesting.

Due to the terrible quality of the camera in my old cell-phone... It is difficult to see the #16491 seal clearly.

All of the #16491 seals that I currently possess, actually have the oil grooves/ ridges, and they go in the opposite direction of the #16542 seals...
The ridges of the #16491 seals are just finer than the ridges of the #16542 seals.

The documentation that GM digitized regarding the 9-Bolt differential are severely lacking in many details.
I went to visit co-workers of mine that work in Archives; and they informed me that detailed information on these axle assemblies outside of info included in the Shop-Manuals...
was always very abysmal. Much of the information never seemed to leave Borg Warner in Australia.

I would like to know more about any type of spacer that you mentioned... because I have had to install shims in this location and would love to see a spacer instead.

 

I wasn't sure about the seals in 16491 with the ridges, I couldn't tell from the picture. That would make them directional then and negate them being universal.
I don't even know where my spare set of seals are to go looking at them again. I have sh*t all over the house.

I just used washers to space out the retaining plate. Nothing fancy needed

How many of these seals did you purchase? lol

 

I have 14 of each.

When I come across a part for something that I need for my business or personally own; and it is rare...
I tend to purchase a good amount if available.

As old and uncommon as 9-Bolt parts are... I have obtained a good amount of some nice stuff:

-29 and 31 Spline Cones and Side-Gears
-Cross-Pin and 4-Spider Assemblies
-Carrier Half 10.9 grade Bolts
-ARP Studs and Nuts for the Bearing Caps
-Fel-Pro Inspection Cover Gaskets
-TA Performance Inspection Covers
-Solid Pinion Sleeves
-ETC...

I used to specialize in 9-Bolt and Dana-44 Swaps in 3rd-Gens.
Most of the Diff. work that I do now is 12-Bolt or 9+ (9.5", 10", 11" versions of the Ford 9")
So now I just keep some of these parts for myself.

Most people here don't know... But I have a Custom Power-Train Business.
I design/ spec. and build complete GM power-trains for "Drag-Week" type "Street-Cars" and Drag-cars in the 1,000 to 3,500 HP range.
Engine-management and power-distribution systems included.

 

Scooter, Thank you for the information.

Yes I see that Summit-Racing sells both axle seals under the Yukon-Gear Branding for $42.00 each...
Not bad, and not crazy priced yet anyway.

Then I also found an earlier thread here on TGO...

Napa offers the Left-side axle-seal, from SKF for $19.99 each. Napa part #NOS 16491.
Autozone offers the Right-side axle-seal, from Timken for $19.99 each. Autozone part #710179 /SKU #226673.

The Reviews for the Autozone part state that sometimes the seal is an all-black seal that resembles the Timken Pinion-Seal for the 9-Bolt...
And other times the seal resembles the SKF seal.

I am going to purchase one of each just to compare to the seals that I already possess... they should be the same.

Do you have any photos of the axle retaining plate installed with the washers that you use?
What is the dimension/ width of the washer/ washers that you use?

 

So YOU have them all! I am going to PM you about the D44

From the picture the NAPA one should be correct, it has that bell shape to it, not square like the other seals

The Timken seal 710179 is like those first ones you pictured, but covered in rubber. That will work, but it is not the correct seal. I have ordered it twice now and gotten the same thing, as have other people and posted here they got the "wrong" part.
I don't have any pictures of the retainer plate with the washers. I just stuck enough in there to get some pre load on the seal, but not enough to crush it. Been good for 2-3 years now?

$42 is pretty crazy considering I think I paid less than $15 for the SKF seals not all that long ago, maybe 5 years.

 

Confirmed. the ridges are slanted in opposite directions

 

What part numbers did you purchase?

 

I just ordered mine today so here is a pricing update: $595AUD for the differential and $185AUD for shipping for a total of $780AUD. I paid via Paypal and that wound up being $644USD. Looks like total price has gone up $100USD.

 

Hey guys, so yesterday I took it upon myself to call one of the diff manufacturers here to see about getting one custom built. The diff I was thinking about is a wavetrac system, unfortunately, they dont do custom orders unless there is a big enough market. The magic number is between 20-40 before they'll do investigation of coming up with a diff for our 9 bolt. I just thought it would be cool if we were able to get one in the US, that way if they need to be serviced we can source it immediately rather than wait to drive our 3rd gens. Let me know what you guys think.

 

That's a nice pipe dream, but I don't think we would ever be able to get enough people to get them to make one. I wish they would make one for the D44 for the C4, and now that I have an F Body D44, I would love to get one in there too

 

the left real seal is circled in blue.

 

I think a far simpler solution is for one of the big third gen resto parts businesses to import the Australian Torqueline differentials directly and carry an inventory for people in the U.S. to buy from.

 

I think a far simpler solution is for one of the big third gen resto parts businesses to import the Australian Torqueline differentials directly and carry an inventory for people in the U.S. to buy from.

 

Go ahead if you think it's that simple

 

Someone needs to figure out who in China is making them. They will sell anything to anyone once you contact the factory directly. Just need to contact a seller on Ali Express probably and have them track down the manufacturer.

GD

 

The part number (30267) does not work, when using the AutoZone website...

Does anyone have an idea about this... or has anyone been able to find part #30267 on the AutoZone website?

 

https://shop.advanceautoparts.com/p/...archTerm=30267

 

Yukon YMSG1001

GD

 

Lol!

That is a Hyperlink for Advanced Auto Parts...
I was asking about AutoZone, like on the receipt that was posted.

 

Correct. It doesnt work online or in the app. You have to go into a store and look it up. It will appear.

 

 

Quick question, finally getting my unit put together, what is the best lubricant for this unit?

Also, are these the right seals? Or did something go wrong?



Used this link: https://www.summitracing.com/parts/yga-30267

Something tells me I might need to make a return...

It appears I received a YMSF1001
Easy enough mistake I suppose...

 

What does the other side of that seal look like?

 

The bigger seal is for the pinion, i just ordered one from summit 2 days ago.

 

Unless they put the wrong one in the bag that is the correct part number for the axle seal
https://www.yukongear.com/partslist....e+Seals+-+Rear

Pinion seal
https://www.yukongear.com/productdet...px?ProdID=8793

 

You are correct, though, the part number on the bag w/1003 is the pinion seal part number through yukon, so that unit is right. You would just have to send that one back and ask for the opposite side, unless you are taking the pinion out of the housing, i would keep to replace the old one. Nothing quite like axle dope getting flunk everywhere.

 

I'm pretty sure it's the pinion seal for the Ford 10.25, it has F1001 stamped on it: https://www.yukongear.com/productdetails.aspx?ProdID=8783

Kind of a bummer, puts the project on a small hold. It's definitely not the axle seal.

Any word on the oil I should use to lubricate this thing?

 

That's a good catch, it's one digit off, an F instead of a G, could just be someone put eyes wrong on the labels. I would call Yukon and see if they will rectify directly

I put Amsoil 80-90 in my 9 bolt

 

I sent an email to Summit about the seal early this morning. They just got back to me and are shipping the new seal free of charge, didn't even require me sending back the wrong one.

Pretty good and snappy customer service!

2.25ish Quarts should be good right? I ended up getting the TA Performance Girdle.

Did you add any additive for the unit?

 

The GM manual says you only need additive if the diff makes noise while turning. The Amsoil says it has modifier already in it, so no additional modifier unless it makes noise. I couldn't tell you the volume, I just pump it in from a gallon container that I keep refilling.

 

Awesome, thanks a bunch, final curiosity, what is the difference between the RH and LH seal? Is it a size difference? Anything visual that gives it away?

 

The ridges in the seal wipe the oil back towards the housing when the car is moving forward, I think. I guess they thought this was a better strategy than a plain double lip seal to prevent weeping/leaks. You should see grooves or ridges inside the seal that touches the axle

 

The seal on the Left side looks like the seal that Timken produces...
and the seal on the right looks like the seal that SKF produced (the preferred design... but is becoming less and less available).

 

I use Amsoil 75w140 in mine. No additives are required for a Torsen style differential.

GD

 

If you have the T/A cover, it has provisions for fill level, drain, and capacity. The small allen screw in the middle is for indication of oil being at the right level when it starts to flow out. Obviously, the rest is explanatory.

 

Dave over at supafspares suggested 75w-90

Any reason you went so high??

 

Those are actually the instructions on the t/a cover, the big allen screw is for fill, the allen at the bottom is for drainage, and the middle is for level indication, I think they want it to be about a 1/8" below the mark. Also, the t/a covers will hold more fluid.

 

I drive it hard and the thicker gear oil does provide some benefits to film strength, wear, and hopefully a little benefit in lifespan - though generally what breaks these diffs is TRACTION - it's a tiny diff that was designed to "handle" 245 crank HP from the highest rated L98 (through an auto that further reduces power), and I'm running an engine that is pretty near 400 HP (325 at the tires).

So as part of an "overall" attempt to gain the most lifespan and power handling from the diff, I put in the Torsen, added the TA girdle cover, and I run 75w140.... is it going to make that much difference? No - but the cost is the same. I'm not building this machine for ultimate fuel economy so the 1-2% loss from thicker oil isn't important - hell the thing gets an average of about 9 mpg on my daily commute.......

To it's credit - the 9 bolt has "survived" three dead 700R4's, and I BEAT THE HELL out of the car pretty much all the time. I can say that properly upgraded they do pretty well. I have the Motive (Yukon) 3.70 gears, and all my rebuild parts came from RaTech.

I'm likely swapping out the rear end though soon as the Procharger kit is sitting here on my garage floor and it's doubtful it will survive 17x10's, and 550+ at the wheels. I will spare it's life for another project and put in something larger before scattering it on the track.

GD