[missiondude]

Yes, mine always had shavings. I change the fluid every 250 miles with cheap ass Walmart gear oil. First diff lasted about 4000 miles, second one has over 3000 miles on it. You will know there is a problem when you find bearing races and balls on the magnet.

 

[mbrandt1402]

The diff was originally designed for Arctic Cat quads and was "okay" when the 1000 debuted in 2012. With the extra power of the HO or the X and/or if the machine is ridden hard, the diff just doesn't last. Sand-n-Sea has an extra 60 hp on his turbo machine. Missiondude doesn't have aftermarket horsepower, but rides the heck out of his machine at Glamis. These guys (and many others on the forum) more or less had to become experts on what it takes to make the diff last.

Whatever way you fix your machine (rebuild, used or new), treat the diff to the best gear oil you can find (not the best you can afford, because you really can't afford to put just "good" oil in that overtaxed diff). Change it as often as you do the engine oil. It only holds like a shotglass of oil, so a quart lasts a long time.

I'm partial to Redline products and ran Heavy Shockproof while my X was turbocharged. I'm not going to say that it is THE best fluid to use, but the specs of the oil and the machinery that use it are impressive. My magnetized drain plug did not ever look like the pic that wayfer included in post #144.

From Redline:

• Film thickness greater than an SAE 75W250, yet low fluid friction like 75W90
• For heavily-loaded racing differentials and transmissions, problem gearboxes
• Most popular ShockProof product, many racing and specialty applications
• Many performance racing applications like Sprint, Midget, Dirt Late Model and Quick Change Differentials, Detroit Lockers and spools, NHRA Top Fuel and Funny Car rear ends
• Not recommended for most synchro applications due to the product's extreme slipperiness

It is also very pretty.

 

[CodyB2014]

I appreciate everything! My magnet had metal on it and there was a metallic color in the fluid but no metal chunks or anything. It's got 2030 miles I just bought it and this happened the first ride. So I'm hopping I can get away with just replacing # 26, 27, 28, 30 and a new coupler. Cause those gears are toast in the clutch basket

 

[MCR500]

The diff was originally designed for Arctic Cat quads and was "okay" when the 1000 debuted in 2012. With the extra power of the HO or the X and/or if the machine is ridden hard, the diff just doesn't last. Sand-n-Sea has an extra 60 hp on his turbo machine. Missiondude doesn't have aftermarket horsepower, but rides the heck out of his machine at Glamis. These guys (and many others on the forum) more or less had to become experts on what it takes to make the diff last.

Whatever way you fix your machine (rebuild, used or new), treat the diff to the best gear oil you can find (not the best you can afford, because you really can't afford to put just "good" oil in that overtaxed diff). Change it as often as you do the engine oil. It only holds like a shotglass of oil, so a quart lasts a long time.

Agree 100+%.....
You are only changing 5+ ozs on the quad diff. My 12’ lost one in 2.5K miles and the 16’ almost 3k.
If you drive hard, they get hot as Hell! and just don’t last long term.
Change the oil every 5Hrs and rebuild if it says C-ya and move on.
Oil... I ran BG Ultra Guard 75/90 always. Full synthetic proven to reduce diff temps. Worked for me until it didn’t.
It sucks Text Ron is not supporting the OG models with a good parts supply.

FWIW
C-ya!

 

[omsontin]

Looks difficult to do

 

[AZwildcat16]

Just completed my first diff rebuild at 5k miles on my 2016 4x ( i bought it with 2500miles). Desert riding in the winter and fire roads in the summer with a few seasonal trips to Glamis. Some of you are complaining of the pinon gear nose being turned down and damaged on teardown. Mine was down to 13mm but the teeth were in good shape. Since I could not get a pinion gear without a backorder I ordered item #4 on my below list PN 2423k58 from McMaster Carr. Turn your pinion shaft down to 12mm and install this hardened sleeve. Now you can use the SKF 15/16 bearing and you saved the pinion. Just measure out the bearing sleeve and leave the shaft just a hair larger so you have a press fit. Once installed the shaft diameter will be 15mm and case hardened.

The other parts on this order were to rebuild the tension on my SLD pack since it was damaged in the carnage. The snap ring and top two thick washers were gone or chewed up so items #2-3 are replacements that fit very well and take up all necessary room. They allow you to load the clutch pack and install the snap ring properly with a lot of tension on it like factory. Vise/press is still needed for install. I got it all assembled inside the basket, half seated the snap ring and then used a press with a socket to push on the snap ring unit it pressed the pack down and let the snap ring into the groove. This ring is thick enough to match the pinion shaft groove perfectly.

Item #1 on the list is shim material sold in 5 packs. Shims for the diff were on back order so I bought these, exact same size but no chamfer. I chose to run them and see no issue with their use. Fit was perfect except the missing chamfer. I used this shim on the long side of the ring gear to set backlash tighter and the factory shim on the short side ( thicker shim ) to set end play correctly.

Other than the SKF needle bearing I bought the ALL BALLS kit and will be running their seals/bearings.

Hopefully this info will help others as their diffs continue to need service.

Thanks to Robert ( Sand n Sea ) for the excellent OG post and the help when privately messaged about Diffs!

 

[izom]

...so beside the sld how was the condition of the rest of the diff?!

 

[AZwildcat16]

It was pretty ugly. I did not take a lot of pictures but the pinion needle bearing drove the failure. It was completely gone. The two cast tabs that hold the needle bearing from moving too deep in the case were busted out and I had to weld a bead in that area of the case to re form the bearing stops. The pinion nose was 13mm and stock it is 16mm so i turned it down to 12mm on a lathe and added the sleeve I mentioned. The pinon ball bearing was gone all but the outer race and all other bearings were locked up tight. The ring gear contacted the case and so did the pinon but i cleaned the gears up as well as the case with rotary bit and scotch brite wheel. I then used dye penetrant to check the gears for cracks. Everything cleaned up well and went together nicely. I had to adjust shimming from factory but all backlash/end play and thrust button checks are within specs. I expect many more miles out of the unit.

I had to drive about 7 miles in 4x4 with the front diff to get out of the sand dunes and back to a place where a trailer could access. So all things considered the car did well and the diff had less damage than I expected to find after being ground to a pulp for that distance.

If someone has a donor gear case that they think is too far gone I would like to do an experiment. I want to take the L/H lower side of the case ( drivers side between the drain plug and forward bearing area and cut it open then weld in a larger cavity as there is plenty of room in the cars frame for this. A mod like that would allow the diff to hold over twice the standard amount of oil which should help tremendously with cooling and longevity.

 

[ARG]

Hey guys, I got a question/observation. My X has 29XX miles, and I just tore apart the rear diff for a pre-failure "maintenance" rebuild. Some moderately rough bearings, especially pinion ball bearing, some wear on the button, but nothing dramatic. However my pinion nose shaft was rough and wore enough for me to replace it. While searching online Rocky Mt has in stock, and I noticed there is a (HT) in description. Are they now heat treating that shaft, or is that just the gear teeth? Anyone order a pinion recently and notice if that nose shaft on the pinion looks heat treated and/or harder? But at least I can turn my used one down and get the SKF needle bearing for a spare.

I'd typically start a new thread but wanted to keep the info on here, as it is full of great diff info, thanks especially to @Sand-n-Sea for making it!

 

[2014 wildcat 4x 1000]

I rebuilt my case as instructed. Had to buy a new case due to dmg from the exploded needle bearing and pinion bearing..
All installed and now it wants to move with Rev of the engine, but its not engaging in forward, reverse, high or low. Will engage when in 4x4, assuming it's only the front that is engaging.

Any advise I may have over looked?

 

[Sand-n-Sea]

No magic with the rear diff. With shifter in "N" jack up the rear of you cat so the rear wheels are both off the ground. Turn a wheel by hand and the other wheel should turn as well. The Stubby Driveshaft/Coupler should also turn. The rear diff gets forward/reverse power directly from the rear stubby driveshaft/coupler. They are always engaged to each other. That coupler turns per what gear is selected. Shift to "H" and turn the tires again. The tires should bind quickly and not turn because the engine is now engaged. If the wheels still turn, check your rear coupler is not broken and is fully engaged into the rear diff (with grease). Check that your shifter/shift cable are working. It might be that you messed with the SLD during your rebuild and it is slipping and not reassembled properly.

 

[2014 wildcat 4x 1000]

No magic with the rear diff. With shifter in "N" jack up the rear of you cat so the rear wheels are both off the ground. Turn a wheel by hand and the other wheel should turn as well. The Stubby Driveshaft/Coupler should also turn. The rear diff gets forward/reverse power directly from the rear stubby driveshaft/coupler. They are always engaged to each other. That coupler turns per what gear is selected. Shift to "H" and turn the tires again. The tires should bind quickly and not turn because the engine is now engaged. If the wheels still turn, check your rear coupler is not broken and is fully engaged into the rear diff (with grease). Check that your shifter/shift cable are working. It might be that you messed with the SLD during your rebuild and it is slipping and not reassembled properly.

I'm pretty positive the SLD is not assembled correctly. It came out when cleaning and wasn't aware there is a specific way to reassemble. It seems to go in easily in many positions.
Are there identifiers on it to know if it was assembled correctly?

 

[Sand-n-Sea]

Did you take the SLD apart? it is a basket with a compressed clutch pack in it. If you didn't take it apart it should be ok. If you did take it apart, then it must be compressed to get the large circlip back on. If you took it apart then that is your issue.

 

[2014 wildcat 4x 1000]

Did you take the SLD apart? it is a basket with a compressed clutch pack in it. If you didn't take it apart it should be ok. If you did take it apart, then it must be compressed to get the large circlip back on. If you took it apart then that is your issue.

Just the clutch pack out of the basket. Didn't touch the clip or individual clutches etc.

 

[2014 wildcat 4x 1000]

Did you take the SLD apart? it is a basket with a compressed clutch pack in it. If you didn't take it apart it should be ok. If you did take it apart, then it must be compressed to get the large circlip back on. If you took it apart then that is your issue.

I'll check the driveshaft sleeve tomorrow and test as you explained.

I appreciate your response and knowledge.

 

[Sand-n-Sea]

Then I don't think that's your issue. Is the stubby driveshaft/coupler fully engaged into the rear diff? Are the splines that engage possibly worn? Do the check of turning the rear wheels while jacked off the ground.

 

[2014 wildcat 4x 1000]

So I've tested a few things. The coupler for the rear drive shafy is fine. When I jack up the rear in park the wheels do not move as expected. When in R, H, or L it moves the motor are trans as expected. When turning the wheels in N both move the same direction. I started her up while jacked up and the wheels move but it's still like it's not fully engaged. When the car is on the ground and put into R, H, L it wants to move but doesn't.
Open to any suggestions?

 

[Sand-n-Sea]

Full power does not seem to be getting to the drivetrain. I would look at the clutching next. Is the correct belt being used?

 

[2014 wildcat 4x 1000]

The belt is an artic cat oem and about 3 trips old. And it can't be the clutch as the front diff has 100 percent power when engaged.

 

[mbrandt1402]

I think you need to re-do your test of the coupler & SLD and also verify that the bevel gears are still working. The bevel gears take the power from the transmission and applies it to the driveshaft running to the front diff and the coupler running to the rear diff.

Bevel gear test: the barrel of the coupler is visible between the rear of the engine and the front of the diff. With the rear wheels off the ground, your X in 2wd and in L, H or R, rev it up to engage the clutch and see if the coupler is turning. I would go so far as to try to stop the coupler by holding a piece of wood hard against the barrel of the coupler, sort of like an inside-out drum brake. If the coupler turns, your bevel gears, which are located in the engine crankcase, are okay. If the coupler doesn't turn or if it can be held stationary while the clutch is engaged, power isn't flowing through the bevel gears to the rear coupler.

Coupler / SLD test: The small male splined end of the coupler slides into the female splines of the SLD. Couplers usually shear off the small male splined end when they fail, or strip the splines. Both of these failures are out of sight, right at or inside the input of the rear diff. With the rear wheels off of the ground, put the X in Park and try to rotate a rear wheel (they will both turn, as you noticed in your prior testing). Put some effort into it - perhaps by using a lug wrench on a wheel nut. If the wheel turns at all, the coupler or the SLD is broken.

Either of those parts could possibly have a "friction fit" between the broken pieces, such that the engine could turn the rear wheels when the machine is in a drive gear with the wheels off the ground and the clutch engaged. A sheared coupler or stripped SLD fits your comment that the X tries to move, but can't quite get going. I don't know of a way to 100% determine if it is the coupler or the SLD without dis-assembly, though an SLD usually pops and bangs when it fails.