Pinion Nut Torque With Solid Spacer

[SteveWK]

I have a solid spacer for my gear install. Does anyone know what torque spec should be used for the pinion nut? Ratech says 125 ft-lbs, but if I am not mistaken, the pinion nut takes considerable torque to tighten all by itself.

Thanks,
Steve

 

[2011 gtcs]

Hope this helps out

 

[Snoopy49]

That torque seems to be a bit light. I called Randy's and they suggested 200 ft-lbs, this was for the Yukon solid spacer. I sent an e-mail to Ratech for verification and I will post back with the results.
It appears to just be the torque for determining pre-load, not final torque.
Ratech uses the same 125 ft-lbs torque for the initial torque when determining the pre-load on all their solid spacers for multiple brands, Ford, Chrysler, AMC and GM.

 

[SteveWK]

Thanks for the info guys.

I should have investigated this sooner as the car goes into the shop tomorrow. I think 125 is lite too, or at least from what I have read online. I've watched lots of youtube videos on this install and it takes gobs of torque to crush that crush sleeve. I'm thinking torque required to turn the nut + 200, measure preload, rinse and repeat as necessary. I don't think the brand of spacer would make much difference unless they use different metals that compress differently.

I just hope the shop will do what I say. Speaking of which, I did ask them to measure pre-gear install backlash and pinion preload. My 3.31s whine some, and I have never launched the car or even know how to use launch control. The rear also clunks on and off throttle. It didn't do that when it was new.

 

[Snoopy49]

This is from the Ford Racing M-4209-8.8 8.8 Ring and Pinion Installation Instruction Sheet

Recommended minimum torque, and this is for the crush spacer.

"STEP 6: Minimum torque required to tighten pinion flange nut to obtain pinion bearing preload, 140 lb-ft."

 

[Snoopy49]

This is from Strange
Pinion nut torque 200 [ft-lbs]

R5230PS-Ford-8.8-Pinion-preload-spacer-kit.pdf

 

[Snoopy49]

From the 2014 Mustang Service Manual
Pinion bearing preload 1.8-3.3 Nm (16-29 lb-in)

New bearings require more preload than used bearings.

 

[SteveWK]

Looks like 200 ft-lb is what I'll have them use.

 

[Snoopy49]

Make sure they cleanup the edges on spacer and remove any burrs. This has been a problem in the past.

 

[Mojo88]

Please keep us all updated. My rear whines too. I measured my backlash at .018" (while I was changing diff fluid), which is over spec. I'm very curious to see what yours is before they rip it all apart.

When I re-do mine, I think I will go for the solid spacer too.

 

[SteveWK]

Dropped the car off. Hopefully I will have some answers in a few days.

 

[RedVenom48]

Solid spacers are great but a bitch to get correct preload on the pinion bearing. Last year when i did my gears i tried to use a solid spacer. After 2 hours of futility, i threw it in the garbage and installed a crush collar.

 

[SteveWK]

Got the car back with 3.73s. It does whine. It whines between 50 and 70 mph and then seems to go away. I couldn't do much testing because of traffic and won't really have a chance to drive it until tomorrow or Sunday, but it does whine. It is loud enough that it bothers me. I don't think it should whine at all right out of the box.

Now for some numbers:

Stock 3.31s prior to removal

• Backlash - 0.012
• Pinion Bearing Preload - 25 in-lb

New 3.73s

• Backlash 0.010
• Pinion Bearing Preload - 20 in-lb
• Pinion Nut - 180 ft-lb
• Solid Spacer

I have to qualify the pinion preload on the new gears. I stopped by the shop and they had the pinion installed at 25 in-lbs and 180 torque on the pinion nut. I found out today after they installed the pinion seal the torque measured on the pinion jumped to 35 in-lbs. They then reshimmed the solid spacer so it had 20 in-lb with the pinion seal installed. In my mind this was a mistake. The whole idea of measuring torque required to turn the pinion gear is to measure pinion bearing preload. Who cares what the pinion seal adds to the party since it is not contributing to the pinion bearing preload. Thus I believe the pinion bearing does not have enough preload.

The whine is not as loud as some I have heard on YouTube, but it doesn't exude quality in my mind and they charged me $1k for the install since my rear suspension mods required more work to remove (torque arm and watts link).

On the bright side, love the gear. I use to fear the gear and was debating between 3.55 and 3.73. I now wonder what a 3.90 or 4.10 would be like in this car. 2nd gear with Toyo R888s and some basic mods is just a complete riot.

You have all been helpful and I will keep you up-to-date as this progresses. I don't think I'm truly going to be satisfied unless I do it myself, but time will tell.

 

[Mojo88]

Got the car back with 3.73s. It does whine. It whines between 50 and 70 mph..... It is loud enough that it bothers me. I don't think it should whine at all right out of the box......

..... I found out today after they installed the pinion seal the torque measured on the pinion jumped to 35 in-lbs. They then reshimmed the solid spacer so it had 20 in-lb with the pinion seal installed. In my mind this was a mistake. ........

First off, thanks VERY much for posting all those numbers. Two thumbs up for that!!!

Very disappointing to hear about the whine. I have a local guy who has installed MANY ring/pinion sets and he says some are more prone to whine than others, even when set up perfectly. I would assume you used Ford Racing parts???

Interesting observation on their preload procedure. Perhaps an 'expert' on here can tell us proper method????

Good luck with it and please keep updating this thread as you go along. Thanks!

 

[Snoopy49]

This is from the Strange pdf I posted above.



Setup specs

Pinion preload 20-25 [in-lbs] (without seal)

Pinion nut torque 200 [ft-lbs]

 

[Snoopy49]

Maybe this will help.

Driveline System Diagnosis and Testing.pdf

 

[RedVenom48]

3.73s... its just something about that gearset that makes noise in the S197 3 link. My 4.10s make a little noise after making a few passes on them last year, but nothing like the 3.73s.

Going to 4.10 would limit your top speed to under 200mph... but unless you routinely go that fast, you'd be very happy with 4.10s.

With slicks and prep, 4.10s and the 2.90 first gear in my 2011 is like engaging warp speed.

 

[SteveWK]

Thanks for the additional info everyone.

After reviewing the 2013 Mustang Workshop Manual I have on CD, it looks like the pinion seal is installed when measuring pinion bearing preload. So, that part of the install is correct. I also went over to the shop a few hours ago and spoke with them. They assured me the ring/pinion gear pattern was good. I guess I could check it myself along with the carrier bearing preload - not sure how to do that exactly. Those two items wouldn't require disassembling the guts of the differential.

From Snoopy49's pdf.

• Condition: Howl — can occur at various speeds and driving conditions. Affected by acceleration and deceleration

• Possible Sources: Incorrect ring and pinion contact, incorrect bearing preload or gear damage

Lexustech48: 4.10s would be interesting. I experienced something new today. There is a bridge near where I live that has that roughed up concrete on it and my R888s really dig into it. While WOT in second, I could feel the whole car lift up. It was an odd feeling and never did that with 3.31s, but I guess my torque arm is doing its job

 

[Cman01]

After they ran the pattern were you there? If you were they could've called you into the shop to take a look at it and also get a pic of the pattern so you have that on record.

When I get my 3:90's in next month I'm waiting for it to be done at the shop and the owner there (who will be doing the install) said he will show me the gear pattern when they get to that part of the install and I for one for sure am going to take some pics of that pattern.

 

[Snoopy49]

Thanks for the additional info everyone.

After reviewing the 2013 Mustang Workshop Manual I have on CD, it looks like the pinion seal is installed when measuring pinion bearing preload. So, that part of the install is correct.

The workshop manual assumes you have a collapsible spacer and it would not be possible to set the preload without the seal since you cannot remove the pinion nut without installing new collapsible spacer. When using a solid spacer, you can adjust the preload without the seal and then install the seal after the preload has be established.