If you grab the yoke and wiggle it, does it move? If the answer is yes, then the pinion bearing likely came apart inside and took the seal out. If the pinion does not have movement then it’s likely just a bad seal. Either one will require removing the diff to fix.

 

It has a little bit of wiggle. I am going to pull the diff and disassemble this week end to check all three bearing and sprag assembly. As well as replace the factory carrier bearing. Hard to believe the bearings would fail at 2,800 miles. I ride fairly easy on what I would say is mild trails.

 

While I’ve heard of some replacing the seal with the diff in the car I would pull the whole thing and do a full bearing job while you’re at it.

 

Pull the diff out and replace it.

Pull skid plate. Disconnect front shaft (remove roll pin) Remove winch. Some people pull the right side axle only. I pulled both (its easier) remove front diff. Gives you a chance to lube the splines and grease the wheel bearings any-how.

You don't have to take the diff apart.

It really isn't as hard as it looks.

 

Thanks for all your input! I will keep you posted. Few more questions though. Where do I find the part number for the diff? Does the Trails and Rock have a factory plastic sprag or aluminum? Anyone know off hand the torque specs for the diff bolts (case and mounting)?

 

P.S. I have a Colorado trip planned next month so I want to make sure I am covered and not have any issues.

 

There should be a sticker on the diff with the part#. It should start with 133XXXX. Sprague should be aluminum. My manual says 9 ft lbs on one page and 11 ft lbs on another for the 6mm side cover bolts, I’ve always done the low end at 9 ft lbs and never an issue. The four 10mm mounting bolts are 35 ft lbs, do yourself a favor and get the longer bolts.

Heavy Duty RZR/General Diff Bolts

These bolts are higher in strength, 10.9 versus stock 8.9, and 30mm in length as opposed to the stock 20mm. The extra length allows more thread engagement in the aluminum differential housing. Th…

rockreadyutv.com

If you decide to do all the bearings and seals, Sandcraft sells a nice kit that includes SKF bearings, SKF seals and a hardened ring gear pin.

 

Awesome thank you!

 

2018 TRE front diff. # 1333791

Man, you did good! you got a lot of miles out of your rig before such problems. I think I was at 500 miles when my bearing cage tore the seal like that. Shortly after that the seal was torn all the way around. I was in Colorado on long expedition trip. I managed to finish a few more days of rides by filling it everyday before heading out for short 40 mile days. I filled it with 90wt, 15w40 Rotella whatever I had on hand to get by since town was 50 miles away. 90wt slowed engagement up some nasty climbs, but it still got me to camp everyday. Don't recommend letting it run dry. Got some plastic shims that will melt if run dry.

Order the sandcraft diff parts and fix it right. See my thread on these problems here.

TRE Front Diff Bearing Failure

It finally happen. China pinion bearing in front diff failed. The metal cage of the bearing came apart and ate the pinion seal. I been towing an expedition trailer and such in Colorado for weeks. I did a service of fluids at 400 miles and everything was working good, but noticing some oil...

www.rzrforums.net

 

Thanks.....I will take a look.

 

FYI,
My pinion bearing never had any slop even with metal bearing cage torn out. Metal cage bearing is bad idea for the pinion. Too much flex under load for such design. Output hub bearings seem to be fine with metal cage. However, the upgraded Sandcraft units had more metal balls and thicker race with more surface area for side loads.

The parts I think matter most are in this order:

• SKF Pinion bearing with Phenolic resin cage
• Grey seal in Sandcraft kit seems more robust, higher silicone like material
• Metal pin in kit is much stronger, my OEM pin was slightly bent
• Must fix the output hub plugs that leak or upgrade to newer design $$$$

If you have as much metal on your magnetic plug like I did you may need a new sprag assembly. I got away with H springs. Had some history marks and broken spring. Everything else was serviceable.

Post up your results. Need to share info on such issues.

If you find something better than the Sandcraft bearing kit please share that!

SKF Explorer Bearing from Sandcraft has Phenolic resin Cage.
From SKF:
This material can withstand heavy inertial forces and operating temperatures up to 120 °C (250 °F). ... Cotton fabric reinforced phenolic resin is the standard cage material for most super-precision angular contact ball bearings.

 

You will need to address this issue while in the diff. Hope this info helps.

Top Secret Updated Front Diff Output Hub

I'm stealing this Top Secret info from Turbo thread so the TRE guys can find it easy. Not 100% sure it fits TRE, so contact Partzilla to confirm. They may have the hub for the TRE with this new design, but I think this fits our rigs since they have the Turbo parts. It might even be possible...

www.rzrforums.net

 

Update:
Front pinion bearing failed. I ordered the Sandcraft bulletproof DIY kit, Sandcraft diff shim and a SuperATV carrier bearing. Case all looks good so I am going to reuse it. I will post more pictures after I get parts. The ring and pinion gears both look good. The two axle hubs were stuck together. that was a challenge to get apart without damaging the sprag or sprag springs. The sleave that connects the two hubs has some micro grooves and a little bit of a rolled edge. Smoothed it out with some 1000 grit.

 

I'm having flashbacks looking at that bearing cage! Not good.