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S197 @4o6racing Build Thread Profile - S197 Mustangs

570
722
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SoCal
I used the FP M-4210-C3 install kit, which includes the GT500 high torque inner pinion bearing (the 2012 and older GT500). All bearings and races were matched sets in the kit. I verified the race #’s and sizes against the ones that I removed and everything matched. I didn’t have a feeler gauge thin enough to check clearance between race and housing, however I’m confident it’s fully set based on the change in sound when I was tapping them in.

I do have the old bearings, but I cut the cage and rollers off the inner pinion to use as a press collar for installing the new bearing.


(Side note: the wheel bearings in this kit are wrong for the S197 - they’re the smaller diameter used in the SN95 cars, should have just ordered the M-4210-B2 kit)
 
3,606
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OK, I was going to suggest you assemble it with the old bearings just to see what happens. These are usually just not that difficult and it looks like you covered all the bases.
 
570
722
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Time Attack
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Under 3 Years
SoCal
The more I read, the more I’m convinced Ford’s instructions are wrong. Everything they describe is characteristic to a face-milled gear set, which these gears are not. For a face-hobbed design, the correction to drive-side heel, coast-side toe would be a thinner pinion shim, which validates I should have just replicated the OE shims that were in there and not messed around with trying to measure??!!

Hey, I signed up for an education when I decided to invest in tools and not just pay someone to set this up for me. It may take me $50+ in pinion nuts and crush sleeves to get it right, but I refuse to give up until it’s right and I understand how we got there. Just frustrating that Ford would make an error like this in their instructions.

DC091CAF-9BE8-48AD-B471-0D5CB970748F.gif
AC3E11FC-F7E2-4A02-8323-BF94C3DC88BA.gif
 
3,606
3,425
You know, and I respect you for doing that, back when I was heavily involved in the ISCA show car circuit I always drove my creations to the show, I refused to trailer my stuff, anyone can pay somebody to do something, dig in, get dirty, nothing decent on TV these days anyway.. drag your kid out with you while you're at it.
 
Hey, I signed up for an education when I decided to invest in tools and not just pay someone to set this up for me. It may take me $50+ in pinion nuts and crush sleeves to get it right, but I refuse to give up until it’s right and I understand how we got there. Just frustrating that Ford would make an error like this in their instructions.

I completely understand..

20201219_095725.jpg

20201220_124713.jpg
 
570
722
Exp. Type
Time Attack
Exp. Level
Under 3 Years
SoCal
Alright TMO Team,

Decided to leave the really expensive new OE cast carrier shims in their bags for tonight, and instead sacrificed another pinion nut & crush sleeve - all in an effort to hopefully prove the FP instructions are incorrect. As I mentioned earlier, it took me 3 tries at the pinion preload to this point. That’s a few times in and out on the pinion seal, and the last thing I want is for that thing to leak - knowing now the work to get to it. Decided to replace it again as insurance.

Alright, pulled the pinion, pressed the new bearing back off. Removed the .0475 shims, then de-burred and measured a new stack at .0375. Slightly thicker than the originals, however backlash was just a tick out of spec when I disassembled at .013”, and I knew the thicker pinion shims brought the backlash to the tight end of spec. So decided to go slightly thicker on the pinion to hopefully pick up .001-.002 of backlash, yet keep an acceptable gear pattern.

Pictures are worth a thousand words:

Drive side:
F1F2691B-1DAD-4B89-8C01-8E3724EE6BBD.jpeg

Coast side:
FCDA7B4D-7800-4B6F-8114-C852E05E9524.jpeg

And backlash:
F65E3343-166D-45C3-B98A-8C8B1CB2E373.jpeg
B317CF4B-3A95-45F6-B8E0-7E4106306AFA.jpeg

It definitely moved the pattern in the direction needed on both drive & coast, and the backlash is now at .0115”, just under the high end of spec, and per @blacksheep-1’s guidance, should be optimal for less heat generation.

What do ya think, button it up and send it??
 
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Nice! How many pinion nuts & crush sleeves for you?

So, i bought two inner pinion bearings and made one a setup bearing so i could slip it on and off while i figured out the pinion shim. During that process i used the original crush sleeve/pinion nut and snuck up on it when testing.

Then i got my carrier shims figured out and after much agonizing over the tooth pattern, i put it together with the new crush sleeve and pinion nut. I too also have way more tools now than i planned. Haha

Alright TMO Team,

Decided to leave the really expensive new OE cast carrier shims in their bags for tonight, and instead sacrificed another pinion nut & crush sleeve - all in an effort to hopefully prove the FP instructions are incorrect. As I mentioned earlier, it took me 3 tries at the pinion preload to this point. That’s a few times in and out on the pinion seal, and the last thing I want is for that thing to leak - knowing now the work to get to it. Decided to replace it again as insurance.

Alright, pulled the pinion, pressed the new bearing back off. Removed the .0475 shims, then de-burred and measured a new stack at .0375. Slightly thicker than the originals, however backlash was just a tick out of spec when I disassembled at .013”, and I knew the thicker pinion shims brought the backlash to the tight end of spec. So decided to go slightly thicker on the pinion to hopefully pick up .001-.002 of backlash, yet keep an acceptable gear pattern.

Pictures are worth a thousand words:

Drive side:
View attachment 62511

Coast side:
View attachment 62512

And backlash:
View attachment 62513
View attachment 62514

It definitely moved the pattern in the direction needed on both drive & coast, and the backlash is now at .0115”, just under the high end of spec, and per @blacksheep-1’s guidance, should be optimal for less heat generation.

What do ya think, button it up and send it??

Since you will be racing, send it. Just remember to check after a few track days. Since they are new gears, that backlash will grow a bit as the gears wear in. Shouldn't be much, but since you left it on the high side for heat purposes, which makes sense when racing, you just dont want to be out of spec later on.
 
3,606
3,425
So, i bought two inner pinion bearings and made one a setup bearing so i could slip it on and off while i figured out the pinion shim. During that process i used the original crush sleeve/pinion nut and snuck up on it when testing.

Then i got my carrier shims figured out and after much agonizing over the tooth pattern, i put it together with the new crush sleeve and pinion nut. I too also have way more tools now than i planned. Haha



Since you will be racing, send it. Just remember to check after a few track days. Since they are new gears, that backlash will grow a bit as the gears wear in. Shouldn't be much, but since you left it on the high side for heat purposes, which makes sense when racing, you just dont want to be out of spec later on.


I thought everyone had "cheater" set up bearings.
remember if you run out of crush sleeves, you can slide a pinion shim behind it and get a bit more crush out of it.....
if you run out of sleeves
at 3AM
Sunday morning
at the dragstrip..
 
570
722
Exp. Type
Time Attack
Exp. Level
Under 3 Years
SoCal
Quick update for anyone following along - spent a few hours during the week getting everything put back on the housing, and started installing it back into the car last night finishing everything up this morning. With the car still up on the QuickJacks, I ran the car in gear to check for noises or vibrations from the rear end or driveline. All good and whisper quiet, so lowered the car and took it for a leisurely loop out to the freeway and back. All I can say is WOW!!! I knew the diff was making noise, but until (not) hearing this newly rebuilt version, I just didn’t realize how loud it really was. Whisper quiet on both drive & coast, and no clunks or noise of any type on the transition from drive to coast and back.

One other note here and probably a hard lesson learned personally - always use the factory service manual for fluid capacities. I saved a fluid chart for the Mustang that LMR has posted on their site. It lists the 8.8 capacity at 2 quarts. Factory service manual is 2.5 Liters, +4 oz of friction modifier. I’m starting to realize that my bearing failure is most likely from following the LMR chart of 2 quarts on the last few fluid changes. This time I filled the axle while still removed from the car, and pinion angle adjusted to what the car would be at ride height. After 2 quarts in, I lifted each end of the axle up to make sure that fluid ran down to the wheel bearings, and spun the axles to make sure the rollers were loaded up. Pulled the fill plug on the front of the housing, and filled until the fluid just started to walk out over the threads in the plug hole. It took approx 2.75 Quarts, so right in line with factory capacity spec. Feel like such an idiot for not verifying this prior. Oh well, the Torsen swap was planned anyway, and now I know how to setup an 8.8. Just glad that the damn thing didn’t seize up while driving it - on track or the highway...
 
149
121
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Quick update for anyone following along - spent a few hours during the week getting everything put back on the housing, and started installing it back into the car last night finishing everything up this morning. With the car still up on the QuickJacks, I ran the car in gear to check for noises or vibrations from the rear end or driveline. All good and whisper quiet, so lowered the car and took it for a leisurely loop out to the freeway and back. All I can say is WOW!!! I knew the diff was making noise, but until (not) hearing this newly rebuilt version, I just didn’t realize how loud it really was. Whisper quiet on both drive & coast, and no clunks or noise of any type on the transition from drive to coast and back.

One other note here and probably a hard lesson learned personally - always use the factory service manual for fluid capacities. I saved a fluid chart for the Mustang that LMR has posted on their site. It lists the 8.8 capacity at 2 quarts. Factory service manual is 2.5 Liters, +4 oz of friction modifier. I’m starting to realize that my bearing failure is most likely from following the LMR chart of 2 quarts on the last few fluid changes. This time I filled the axle while still removed from the car, and pinion angle adjusted to what the car would be at ride height. After 2 quarts in, I lifted each end of the axle up to make sure that fluid ran down to the wheel bearings, and spun the axles to make sure the rollers were loaded up. Pulled the fill plug on the front of the housing, and filled until the fluid just started to walk out over the threads in the plug hole. It took approx 2.75 Quarts, so right in line with factory capacity spec. Feel like such an idiot for not verifying this prior. Oh well, the Torsen swap was planned anyway, and now I know how to setup an 8.8. Just glad that the damn thing didn’t seize up while driving it - on track or the highway...
Are you using the stock stamped steal cover or the Ford Racing finned aluminum cover? The aluminum covers hold more fluid and using the factory fill chart will short fill every time and lead to bearing failure.
 

TMSBOSS

Spending my pension on car parts and track fees.
6,167
3,151
Exp. Type
HPDE
Exp. Level
5-10 Years
Illinois
On the 8.8 the fill plug at the front of the diff housing pumpkin is the only to accurately fill the diff. Once the fluid starts to drain from the front the housing is full. Filling by volume is always a bad idea when the fill to plug is available.
 
149
121
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
On the 8.8 the fill plug at the front of the diff housing pumpkin is the only to accurately fill the diff. Once the fluid starts to drain from the front the housing is full. Filling by volume is always a bad idea when the fill to plug is available.
I agree. I remove the plug on the front and fill through the top hole on the Ford Racing aluminum cover. I add lube until it starts to come out the front.
 
570
722
Exp. Type
Time Attack
Exp. Level
Under 3 Years
SoCal
Are you using the stock stamped steal cover or the Ford Racing finned aluminum cover?

Great point - I have the Whiteline Watts link. Nothing mentioned in their install manual about a change in fluid capacity - just recommends using the fill plug


On the 8.8 the fill plug at the front of the diff housing pumpkin is the only to accurately fill the diff. Once the fluid starts to drain from the front the housing is full. Filling by volume is always a bad idea when the fill to plug is available.

The main challenge with this is that most average joes aren’t using a 4 post drive-on lift, so the rear axle is typically at full droop when servicing the diff. Even using ramps, all 4 corners would have to be equal height to replicate pinion angle at ride height. Using the fill-plug method with ramps under the rear only would cause an under-fill, and using the fill plug at full droop will cause an over-fill. I agree it’s the best and only way for each specific axle, as long as the pinion angle is considered.
 
570
722
Exp. Type
Time Attack
Exp. Level
Under 3 Years
SoCal
What a difference a year makes. March 15, 2020 - with the world on the brink of Covid-19 lockdown, I signed up to run Chuckwalla Valley Raceway because NASA cancelled their AutoClub Speedway event for the same weekend. It turned out to be one of the most frustrating track days. The 17 turn technical circuit exposed some horrible setup issues that were previously undetected on ACS and Big Willow. The best lap I could muster up was a pedestrian 2:11.6, an easy 5 seconds off cars that I could run with on the open tracks. That same day, @Oxford5pointoh and Dezertnut were throwing down an epic weekend, running lead follow at the front of their run group and going fast lap after fast lap. These guys were validating what a properly setup S197 could run on this circuit.

Fast forward to 2021, and after lots of seat time, sage advice from fellow TMOer’s and lots of setup changes, I was ready for redemption. First session out was a 2:04 - solid improvement over last year, but not nearly close enough to 2:00 to feel good about making a run at sub-2. Each session I was picking up a full second, and I finally figured out a gear strategy at the end of the 3rd session but couldn’t catch a clean lap to validate. Came out in the 4th session with only 1 car ahead of me on grid, and went full send. When the lap timer flashed 1:59.7 after the first lap, I feared that I would drive straight off T2 in excitement! Pulled it together and backed it up with 59.5 and a 59.4. This circuit seems to have a hard barrier on the Sub-2 club, and I was absolutely over the moon with the results. Speed Ventures offered a bonus session at the end of the day, and with most of the paddock gone, there were only 4 cars that went out. @PaddyPrix and I lined up 1 & 2, and checked out on an epic lead follow session for 5 laps. We both improved on our earlier runs, and I finished the day at 1:59.2

Big thank you to everyone on TMO - definitely wouldn’t be hitting goals this quickly without the solid help and guidance found here!

B03D61D4-28AB-4835-974B-2C63D7C5B2D7.jpeg
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