Diff Gears?

[bloodredmaxx]

I am currently running a o.s. rg-x(p) with the stock diff's. The front one is completely stock and the rear diff has a spool. It has a huge turning radius and loves to do donuts. What can i buy or do to my diff's to make them .21 proof. I dont have the money to go 1/8th scale diff's so thats out of the question. Any ideas on what i can do?

 

[Çh®i§tiªñ]

Not much cheaper than 8th scale diffs but check it out. Get just the parts you keep blowing out.

http://www.kippster-racing.com/

Another thing, with stock, you may want to make sure, and double sure, that you have your diffs shimmed properly. When you put a powerhouse to those diffs, the slightest play, will lead to total destruction quickly.

I fill my diffs with white lithium as well. Just plain helps. A little draggy at first but 5 minutes later its warm and fuzzy.

My thoughts.........

 

[bloodredmaxx]

Should i be worried about the spider gears also?

 

[Çh®i§tiªñ]

What do you keep blowing out?

personally, I always wrench the diff cups. If that spider gear pin rips one way or the other you can kiss the spider gears goodbye too. I havent put a .21 kit on yet but could blow em out with a .15 just the same. Until I got a handle on the shimming part.

 

[bloodredmaxx]

I dont keep blowing anything. I have a spool in the rear and the gears are fine. Nothings broken or anything i just want to take the spool out cause it sucks to drive with it. On traxxas message board a guy said he was running a .247 for awhile and his diffs were fine. I think everyones blowing diffs and upgrading to rrp and kipster diffs when the real problem is the case. So for now i'm gonna upgrade to an aluminum diff case and try the stock gears.

 

[Çh®i§tiªñ]

Good thinking! I knew I like you for a reason

I would go with just the cups too had I gone .21 or bigger yet. You may want to just try stock and shim them out right and pack them good with the lith grease.

Then again, if you can lay down the cash, get the cups!

 

[bloodredmaxx]

I think for now I'm just gonna get a diff case and get the hardened spider gears from kipster since money is a little tight right now.

 

[Çh®i§tiªñ]

Way To Go!

keep us posted on how they work out!

 

[bloodredmaxx]

I'll make sure i do that! I have to wait till tomorrow until i can order it. So once i get it installed i'll keep you all posted on how it works out with the torque of a .21

 

[olds97_lss]

I run an OS 21 RG-X(P) on my maxx. I'm running with integy's diff cases and a maximizer diff cup in the rear. I wanted to make sure it's worth the $60 i spent on it before i buy another for the front. Besides, the rear gets allot more of the torque.

The first gallon of fuel ate up the diffs a bit. Not completely toast, but significant chipping of the gears. I have since installed the maximizer diff cup in the rear. I have about 1/2 gallon through it and it seems fine.

Only time will tell.

 

[crower28]

An aluminum diff case is a very good idea. It will keep the gear mesh stable, unlike the stock plastic case.

Below are details on how I prep my diffs. I have approx 11 gal (trx 2.5) on one set up this way. It is way past due for inspection, but it keeps working, and I don't care if it self destructs at this point. It's starting to get a little "loose". I'm using the stock cup and gears and the Al case from that link above.

I'm using lock lube in the cups for better traction and handling.

T-Maxx diff modification:

Here's the grease I use:
http://www2.towerhobbies.com/cgi-bin/WTI0091P?&C=CMH&V=YOK
I use the "hard" in the rear and the "medium" in the front.
You'll need shims too:
http://www.teamcrc.com/
6 mm and 10mm (the 10 mm are for the diff side brngs if you want to shim for better gear mesh)
-Remove and clean out diff cup
-Dry assemble spiders in cup and trial & error 6mm shims to remove excess endplay (should take 3-5 shims). You don't want it tight, so leave a little play (.010"-.020"). Keep the stock plastic washer against the cup. Split the shims side to side (equal # on each shaft).
-Apply lock lube to cup side gear and install into cup w/ shims. fill cup approx. 1/2 w/ lube and install spider/shaft assy. Fill rest of cup, leave a depression slightly smaller than ring gear side gear (try to leave no air). Apply lube to other side gear and install into ring gear w/ the rest of the shims. Assemble the ring gear to the cup (some grease will squirt out).


-If you want to improve ring gear/pinion mesh, now is the time.
-Dry assemble the cup assy. (carrier) into the case w/o the pinion. T & E the endplay w/ 10 mm shims (they go between the brng and the carrier) to .010" - .020". Keep track of # of shims (we'll call this the preload shim pack).
-Install pinion and adjust shims on ring gear side to move the mesh tighter. Put the rest of the preload shims on the other side and dry assemble the case to check. Some tight spots are fine, but you should be able to turn the pinion shaft w/ your fingers. Play w/ it till you get it right, might take a few tries.
-Disassemble and grease ring and pinion. I use this grease, you should be able to find it locally.
http://www.super-lube.com/index.html
-Final assemble diff

-Use a 3/16 id x 5/16 od x 1/16 thick o-ring between yoke and diff on the shaft during assembly. This will seal the diff and enhance the posi effect (w/o the o-ring you will get a glob of lock lube in your yoke). You will have to push HARD on the yokes to get the pins in.

-I also use foam body washers (p/n 4915) on the yoke to dust seal the brngs. Clean the yoke and stick it on. You will have to stretch it slightly to go over the raised area in the center. Apply some grease to the exposed areas of the foam before assembly. The foam will be tight at first, it will loosen up in a run or two.

The medium lube in the front doesn't hurt turn in.

The results holding the truck in the air are:
-spin 1 rear hard, spins whole driveline w/ little hesitation.
-spin 1 front hard, opposite side stays still a sec while rest of driveline turns, and then opp. side catches up
Sounds kinda dorky, but it's the best way I could describe it.

 

[SuperMaxx97]

i run teh XTM 24.7 in my supermaxx and man it was bad to my stock diffs. it would rip the too pieces. so now i have powerline aluminum cases, with all kippster gears. i think i got the whole thing for about $100

bryan

 

[alkyula]

hey how has that diff setup been working for you? I'm about to go from a os .21 rg to the xtm 24.7, and i know ill be needing to upgrade the driveline, and i jsut dont think i can make myself spend 250$ +/- for some UE 7.5 diffs. I'm guessing your doing the whole kippster cups and gears? oh BTW did you find out what you killed inside your tranny? i remember you posting about tranny probs while back. peace--

 

[SuperMaxx97]

the diff setup is good. i like them, but still i want to run the UE 7.5's but i just dont got the money right now. ya they are all kippster gears inside.

i dont know what happened with my tranny. i didnt work for about 2 tanks, took it out the next day and worked perfect.

bryan

 

[alkyula]

haha sounds like the way my 1990 260k miles dodge dynasty runs...doesn't want to go then next day runs like a champ.