[CA 800]

Scott,

Tribal knowledge, past down by word of mouth, from long ago.

There is very little documentation on the internals of rear diff.
Below are a couple of comments from RZR Forums threads.

March 18th, 2013: An engineer with Schafer Driveline, a division of Schafer Gearworks, mentioned that the best possible fix for this as a SURE preventative is to order Polaris part number 7547243 (non-nylock nut with longer threads), use Loctite #277, and torque to NO MORE THAN 250 LB-FT.

I think Loctite #272 is better choice.

and

https://www.rzrforums.net/rzr-800-s...net/rzr-800-specific-discussion/178257-rear-differential-backlash-pre-load.html
Per HPD instruction sheet:
"Preheat the case and tap the bearing races into the case. Allow case to cool. Shim pinion bearings for a bearing preload, measured by torque, to rotate with 7 to 12 in-lbs, when lightly oiled, without seal installed. Torque pinion nut to 275 to 300 ft-lb. with Red Loctite.
Shim the right hand spool bearing for contact patch and .0035" to .007" backlash.
Shim the right hand cover bearing for a bearing preload of .0035" to .007"

Schafer Driveline acquired the Dana/Spicer division that originally made rear diff, and HPD designed & sold an aftermarket rear diff housing.

Polaris' recommendation is to remove and replace complete assembly.
That way the "factory trained" mechanics won't need to torque any fasteners above 40-50 ft-lbs. No need to buy multiple torque wrenches.

 

[RZR_Scott]

Scott,

Tribal knowledge, past down by word of mouth, from long ago.

There is very little documentation on the internals of rear diff.
Below are a couple of comments from RZR Forums threads.

March 18th, 2013: An engineer with Schafer Driveline, a division of Schafer Gearworks, mentioned that the best possible fix for this as a SURE preventative is to order Polaris part number 7547243 (non-nylock nut with longer threads), use Loctite #277, and torque to NO MORE THAN 250 LB-FT.

and

https://www.rzrforums.net/rzr-800-s...net/rzr-800-specific-discussion/178257-rear-differential-backlash-pre-load.html
Per HPD instruction sheet:
"Preheat the case and tap the bearing races into the case. Allow case to cool. Shim pinion bearings for a bearing preload, measured by torque, to rotate with 7 to 12 in-lbs, when lightly oiled, without seal installed. Torque pinion nut to 275 to 300 ft-lb. with Red Loctite.
Shim the right hand spool bearing for contact patch and .0035" to .007" backlash.
Shim the right hand cover bearing for a bearing preload of .0035" to .007"

Schafer Driveline acquired the Dana/Spicer division that originally made rear diff, and HPD designed & sold an aftermarket rear diff housing.

Polaris' recommendation is to remove and replace complete assembly.
That way the "factory trained" mechanics won't need to torque any fasteners above 40-50 ft-lbs. No need to buy multiple torque wrenches.

275 to 300! Jebus man that's tight! I'm pretty sure I'll only go 200 tops depending on my feelings when I see the nut and pinion shaft. "No more than 250" really narrows it down huh?

Maybe the guys at the factory thought it was 250 in/lbs not foot. That would be about 20 ft/lbs, from my reading that is a typical find. Yikes!

Yeah, if I was a Polaris dealer I guess I would just order a new one up and make plenty of money installing it anyway. Then you get to do it again in a 1000 more miles or so too right?

Now that I think about it there isn't much left of it in a typical failure anyway, might as well get a whole assembly being that the case now has a big hole it it!

I'm sure I'm not the first to say this whole thing kind of disgusts me. If I wasn't able to do this myself I would be pissed.

I just changed the gear oil in it too, used the Polaris stuff. This time I think I'll go 75-90 full syn of some sort, maybe Mobile 1.

 

[Pullerguy]

Scott:
You can do the "Pinion Nut Dance" with our draining the oil. Find some plastic plugs that fit the axle ports, stick them and proceed. You can use duct tape also if you can't locate any plugs. Check suppliers that build hydraulic hoses is a good start for the plugs.
Les

We torque the nuts to 250 ft. lbs. when we do one. Research Loctite Red Thread lock, you will find that Loctite 272 is designed for areas where oil is involved, 271 & 277 is designed for suspension fasteners, vey little oil there.
Les

 

[RZR_Scott]

Scott:
You can do the "Pinion Nut Dance" with our draining the oil. Find some plastic plugs that fit the axle ports, stick them and proceed. You can use duct tape also if you can't locate any plugs. Check suppliers that build hydraulic hoses is a good start for the plugs.
Les

We torque the nuts to 250 ft. lbs. when we do one. Research Loctite Red Thread lock, you will find that Loctite 272 is designed for areas where oil is involved, 271 & 277 is designed for suspension fasteners, vey little oil there.
Les

Thanks, going to drain it, just picked up some synthetic Delo 75-90.

Also got the loctite today, 272. I found a socket at Autozone for $11 and cut the end off. At first I was thinking it might not be deep enough but watching your video again it looks like your tool isn't all that deep either, so I welded on two pieces of strap to the socket and will see how it goes. If it doesn't work I will try to find a deep 1 3/4" to modify or maybe add a piece of pipe.

The coupler, o-ring and seal are on the way too. Go figure the only thing I haven't got confirmation on shipping is the nut, guess I should have ordered it from someone besides stupid Polaris

I'm hoping to go riding this weekend since the heat is letting up a bit. Looks like I won't get it done till next week so I'll just cross my fingers. It only has 300 miles on it, I'm betting it will go another 50 or so before I do the pinion.

 

[RZR_Scott]

A little update,

Got the diff out and removed pinion nut. It was VERY tight. I had to pull pretty hard on my tools 3 foot bar to loosen it and it went a turn or two to get past the nyloc part. If it wasn't 200 ft/lbs it was close. Just at 400 miles on the car.

I'm still waiting on the new nut so I can put it back together.

I'm in Bakersfield, Ca if anyone needs the tools.

 

[Pullerguy]

RZR Scott:
ow long is the handle on your pinion nut wrench?
Les

 

[RZR_Scott]

RZR Scott:
ow long is the handle on your pinion nut wrench?
Les

3 feet. It was very tight. I'm guessing on the torque, 200 is my guess.

Wanted to add if someone else does this job. I used a punch to put a small hole in the seal then a wood type screw to pry on with dikes to pop it out. It came out very easy. No need to drill a hole and make metal shavings to get in the pinion bearing.