Diff cups from the factory

[mooman007uk]

Mooman, I have over 4 tanks through the tempered cups as of today. Still holding up beautifully. I am going to tear down the rear end this weekend, probably Friday to see if there are any cracks, twisting or stretching on the cups. Amazing that this may be the problem, i thought it was the dimensions of the shaft with the larger hole for the new pins at first. This is a much easier fix (and a hell of a lot cheaper!) than having cups made or purchasing aftermarkets. On another note I tried the pinion (A) spur(B) swap to see the top speed. Made one pass and changed it back. Way too much clutch slippage! Granted the top speed was really nice but the stress on the clutch isn't worth it. Maybe just a set of 27/33 for a little more. With the 27/33 how much low end will I be losing? If I do that I just may reverse the clutch shoes back to their original spots.

I hope to be running again tomorrow, I must move that slab.


I got the 27/33 lost no low end really that you'd notice,with the ONB RP28.5, 813 and 77dom it hits really quick and keeps going, needs a bit of room as it is pretty damn fast

 

[DemonRC]

I think Rob needs to revise his test person criteria to:


1) 100+ posts


2) If the first 3 letters of your username are M, O, and O, you automatically qualify.


3) If you have a motor anywhere remotely close to Yolanda's 30.5


I don't qualify even though I've been spamming the forum to get to 100 LMAO . Also. my iddybitty DS 26 just don't put out enough torque to break stuff.

 

[Lizardking]

Add me to the list....thanks

 

[speedyd]

i can break stuff with the best of them! i would love to beat on a set.

 

[Rampage.Pete]

damn should i start to spam all threads to get my 100 fulfilled im sure my time comes in time enjoy the samples guys.... hope they are a step up

 

[RampageHopUps]

I ran out of time this week. My LED systems came in Wednesday and I have been fooling around with them. I will go Monday and get them re-hardened.

 

[str8jailbird]

I ran out of time this week. My LED systems came in Wednesday and I have been fooling around with them. I will go Monday and get them re-hardened.

Rob, you need to take a break!lol

 

[mooman007uk]

I'm back together again...like humpty...shall continue testing tempered cups over the weekend. I've 2 in back, a dremeled cup and stock upgrade cup in front for a control...and my TT is on it's way from NC

 

[Clubin]

I will be taking 10 sets over to a heat treater on Tuesday, and we can see if a new hardenss specification will fix the problem for good.
If anyone wants samples, let me know. You have to be an active member with at least 100 posts.

Well, now I can join the club, I broke not one but 2 today, I wasn't even seriously bashing yet. It happened in 2 seperate times, both rear. I'm waiting on a set Rob, I will pay shipping and whatever you think they are worth, I need part's. I used up all my spare parts. lol

 

[kryptonite]

I will be taking 10 sets over to a heat treater on Tuesday, and we can see if a new hardenss specification will fix the problem for good.
If anyone wants samples, let me know. You have to be an active member with at least 100 posts.

hey rob. i wouldnt mind puting a set thru the ringer. i think i have more then 100 posts? but i also run my rigs ALOT.. im out a few times a week. and i also just broke a diff cup..

 

[yolonda21]

Well guys if old man winter dosnt rape us over night, there calling for 6 inches of snow. I will be heading out tomorrow to beat my Rampage, i'm sure i will break one as i am runninf stock diffs. there is a group of about 15 of us heading to the pits......should be fun!

 

[mooman007uk]

I just thrashed mine without mercy and guess what...no broken diff cups! did munch a set of 27/33 mcd gears though???don't know what caused the gears to strip, I'll have to study the vid which will be up tonight, also the exhaust came loose and blew the gasket and I bent my rear body mount i made after one big upside down slap, the desert rat body is real tough...my driving was a bit off today so many oopsies but the body is so flexible it only has a few creases and a small hole in it. No other damage to report, back in the game tomorrow for another go. Love this truck.


everybody...temper those cups and they'll be fixed...i should have broke at least one today.


Clubin do you have the stock cups? dremel them if you do and temper and you'll be sorted.

 

[Clubin]

I just thrashed mine without mercy and guess what...no broken diff cups! did munch a set of 27/33 mcd gears though???don't know what caused the gears to strip, I'll have to study the vid which will be up tonight, also the exhaust came loose and blew the gasket and I bent my rear body mount i made after one big upside down slap, the desert rat body is real tough...my driving was a bit off today so many oopsies but the body is so flexible it only has a few creases and a small hole in it. No other damage to report, back in the game tomorrow for another go. Love this truck.
everybody...temper those cups and they'll be fixed...i should have broke at least one today.


Clubin do you have the stock cups? dremel them if you do and temper and you'll be sorted.

Yes, I broke 2 stock cups. I did some research on tempering. What did you do? Tool steel, which is what I think the cups would be refered to must be cooled by air. Here is some interesting info on tempering- copied from wilkpedia. >To harden by quenching, a metal (usually steel or cast iron) must be heated into the austenitic crystal phase and then quickly cooled. Depending on the alloy and other considerations (such as concern for maximum hardness vs. cracking and distortion), cooling may be done with forced air or other gas (such as nitrogen), oil, polymer dissolved in water, or brine. Upon being rapidly cooled, a portion of austentite (dependent on alloy composition) will transform to martensite, a hard brittle crystalline structure. The quenched hardness of a metal depends upon its chemical composition and quenching method. Cooling speeds, from fastest to slowest, go from polymer (i.e.silicon), brine, fresh water, oil, and forced air. However, quenching a certain steel too fast can result in cracking, which is why High-tensile steels like AISI 4140 should be quenched in oil, tool steels such as 2767 or H13 hot work tool steel should be quenched in forced air, and low alloy or medium-tensile steels such as XK1320 or AISI 1040 should be quenched in brine or water.

 

[mooman007uk]

I heated to beyond blue thru to silver grey and chased it up to the cup, then i let it sit in air to cool slowly, jailbird did his to medium blue. both seems to be working...just stay out of the brittle range, 450-700f and you'll be good to go...silver is about 900f.


I posted a colour chart in one of the diff cup threads that'll give you temp to colour (roughly)

 

[Piranha2]

hmm, I flipped mine, cartwheeled it and yeah Moo, the exhaust came loose, we blew a gasket, already have a broken body mount, landed on the roof, Asgard body fine though, just a few creases, back in it tomorrow. Love this truck.......anyone else got deja-vu???

 

[RampageHopUps]

OK, I have an appointment with the heat Treater tommorrow. He will review the problem and offer a solution.

 

[Clubin]

OK, I have an appointment with the heat Treater tommorrow. He will review the problem and offer a solution.

Good to hear you are on top if it Rob.

 

[str8jailbird]

Great news Rob, can't wait to see the outcome. I'm heading down to beat my truck for a while now. Weather is beautiful here today!

 

[Clubin]

OK, I have an appointment with the heat Treater tommorrow. He will review the problem and offer a solution.

So was there a tempering issue can it be resolved? Curious to hear what people that specialize in tempering thought of it.

 

[RampageHopUps]

I never made it. Then he was on vacation, so I have another appointment tommorrow the 8th.