Anyone else ever had their diff eat the gasket?

[slick2500]

Short story long I'm putting a Hot Racing bulkhead on my K6S EXB and noticed that the front diff had leaked. Well once I opened it up I saw that it was empty then I noticed what looked like little chunks of paper all over the place.

Not sure how that even happened.

 

[Robbbbbb66]

Short story long I'm putting a Hot Racing bulkhead on my K6S EXB and noticed that the front diff had leaked. Well once I opened it up I saw that it was empty then I noticed what looked like little chunks of paper all over the place.

Not sure how that even happened.

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I've had it happen before when I did not align the lsd plates up to the diff case and it spun, destroying the gasket along with it.

 

[HZRDOS]

Yep. Only on the EXB diffs. But since removing the star plates and running open with just two round plates and a shim each side, not had the issue. Somehow those star plates do it.

 

[Surchaufeur]

Thats an odd one

 

[Johnny b]

Nope never! But I had my Losi 5T drop down in a 8 ft water drain cuz some dumbass left the cover off it!!!! off topic...sorry....

 

[Hector_Fisher]

I've had it happen before when I did not align the lsd plates up to the diff case and it spun, destroying the gasket along with it.

Ah makes alot of sense. I was just about to chime in that it happened to me. I know the lsd plates can very temperamental in getting them aligned right when you snap the case shut. I bet it's just too difficult to get perfectly right every time.

 

[Kingleo619]

i been using the stock gasket on my v3 typhon since i joined the forum in 2019 all praises to properly shimmed diffs

 

[Rolannd]

My used k6exb had a chewed up gasket just like that too.

I've had it happen before when I did not align the lsd plates up to the diff case and it spun, destroying the gasket along with it.

Dead on in my opinion. I haven't had a problem with mine after I rebuilt it.

 

[Sandracer_NL]

I've had it happen before when I did not align the lsd plates up to the diff case and it spun, destroying the gasket along with it.

Yup, same here.
Now when I rebuilt a diff I put the diff gasket in the ring gear/spur gear instead of on the diff case edge before putting them together. They other way around is very tricky as it’s a very tight fit between the lsd plates and gasket.

 

[Yonic]

just happened to me in my EXB diff.. and i don't have any LSD plates. i think it might have been a bad batch of gaskets

 

[djsarma]

This happened to several of my exb diffs as well. Each time the 4 ring gear screws backed out of the plastic case threads and the gasket tore off and got eaten up because it was no longer clamped down. Only happened to rear diffs.

Because the flat head screws are conical on the ring gear contact surface, hard impacts hammer and pull the screws away from the case thus loosening up over time. I drive mine hard and noticed this would happen after 5-10 packs. Sometimes my gears would strip too as a result.

The primary solution for me was to shim the diff externally for 0 side to side play in the bulkhead with a tight but non binding fit. This way there is no room for the ring gear to move away from the diff case. I think i also used longer screws in the diff case. To really bulletproof it id recommend aluminum bulkheads and diff case.

 

[slick2500]

This happened to several of my exb diffs as well. Each time the 4 ring gear screws backed out of the plastic case threads and the gasket tore off and got eaten up because it was no longer clamped down. Only happened to rear diffs.

Because the flat head screws are conical on the ring gear contact surface, hard impacts hammer and pull the screws away from the case thus loosening up over time. I drive mine hard and noticed this would happen after 5-10 packs. Sometimes my gears would strip too as a result.

The primary solution for me was to shim the diff externally for 0 side to side play in the bulkhead with a tight but non binding fit. This way there is no room for the ring gear to move away from the diff case. I think i also used longer screws in the diff case. To really bulletproof it id recommend aluminum bulkheads and diff case.

Yeah I noticed some of the screws were loose so I was assuming that was what had happened as well. I think my next investment is going to be aluminum diff cases.

 

[SrC]

Yup, same here.
Now when I rebuilt a diff I put the diff gasket in the ring gear/spur gear instead of on the diff case edge before putting them together. They other way around is very tricky as it’s a very tight fit between the lsd plates and gasket.

+1

This happened to several of my exb diffs as well. Each time the 4 ring gear screws backed out of the plastic case threads and the gasket tore off and got eaten up because it was no longer clamped down. Only happened to rear diffs.

Because the flat head screws are conical on the ring gear contact surface, hard impacts hammer and pull the screws away from the case thus loosening up over time. I drive mine hard and noticed this would happen after 5-10 packs. Sometimes my gears would strip too as a result.

The primary solution for me was to shim the diff externally for 0 side to side play in the bulkhead with a tight but non binding fit. This way there is no room for the ring gear to move away from the diff case. I think i also used longer screws in the diff case. To really bulletproof it id recommend aluminum bulkheads and diff case.

I always assemble and fill my diffs with well "cleaned out" screw holes , then install the (4) very cleaned screws, about 4-5 threads in, Only then will I fill, bleed, then remove the 4 screws, install the gasket onto the Spur or Main gear. Gasket mating surface should be free of oil also, dry surface for the gasket is best. Then close her up. The slightest amount of Diff oil on the screws and inside the Carriers holes threading and on the gasket is NG. Gasket can shift as well if oiled up and will cause the screws to back out under load. OE Plastic diff cups/carriers do wear out after a while. They are consumble parts and cheap to replace. Alloy is an option. But comes with a few other caveats. I prefer Alloy diffs at the center only. Center gets very hot as opposed to the Fr and rear diffs. My FT alloy center diff gets to 250F with 700k oil. Plastic cups would easily melt. Been there. FT Stocker center diff is Alloy out the box, and for this reason, I imagine.
My 2 cents.

 

[LibertyMKiii]

.

 

[slick2500]

Guess who just realized the EXB uses different diff gaskets than the rtr.............



.

 

[speeding_Infraction]

Nope never! But I had my Losi 5T drop down in a 8 ft water drain cuz some dumbass left the cover off it!!!! off topic...sorry....

Did you get it back?

 

[Johnny b]

Did you get it back?

Yes, thanks. Just running in a park and it dropped out of sight. That water drain was 8 ft deep. Car was upright and still idling when I got there. Normal there's water down there but it had been dry, thank God. Scraped myself up getting out of that hole but wasn't leaving without it. Over 15 yrs ago...still pisses me off! Lol

 

[speeding_Infraction]

Yes, thanks. Just running in a park and it dropped out of sight. That water drain was 8 ft deep. Car was upright and still idling when I got there. Normal there's water down there but it had been dry, thank God. Scraped myself up getting out of that hole but wasn't leaving without it. Over 15 yrs ago...still pisses me off! Lol

That'd be quite a sight. Good magic trick to play... Big a$$ rc just disappeares into thin air

 

[djsarma]

Yeah I noticed some of the screws were loose so I was assuming that was what had happened as well. I think my next investment is going to be aluminum diff cases.

I forgot to mention, id recommend you replace the screws if they were loose. They may be slightly bent/weakened from supporting the ring gear load while backed out and may snap off at the head if reused. On my 8s arrma diffs the screws snapped off after i reused them from backing out. My 6s diff screws haven't snapped off yet but I replace them preventatively if they loosened up.

+1

I always assemble and fill my diffs with well "cleaned out" screw holes , then install the (4) very cleaned screws, about 4-5 threads in, Only then will I fill, bleed, then remove the 4 screws, install the gasket onto the Spur or Main gear. Gasket mating surface should be free of oil also, dry surface for the gasket is best. Then close her up. The slightest amount of Diff oil on the screws and inside the Carriers holes threading and on the gasket is NG. Gasket can shift as well if oiled up and will cause the screws to back out under load. OE Plastic diff cups/carriers do wear out after a while. They are consumble parts and cheap to replace. Alloy is an option. But comes with a few other caveats. I prefer Alloy diffs at the center only. Center gets very hot as opposed to the Fr and rear diffs. My FT alloy center diff gets to 250F with 700k oil. Plastic cups would easily melt. Been there. Stocker center diff is Alloy out the box, and for this reason, I imagine.
My 2 cents.

This is great advice, unfortunately in my case everything was dry & clean upon rebuild and it still happened. Imo the main issue is the EXB diffs are using flat head screws. High load and impacts axially along the screw can stretch and force them loose overtime because they are conical on the seating surface.

Regular RTR diffs in this aspect are better because they use button head screws that are only subject to shear forces from the ring gear. My fireteam rtr diffs have been solid with the stock plastic case so far

 

[SrC]

Seems the 8s diffs have loosening issues more so?
I don't own an 8s. But i'm all over the 8s threads.