Advice on diffs and diff cups
 

I got some money to do some upgrading. First you should know that I'm running and HVmaxx with 7 cells 3300's. I've put the UE idlers in already. I plan upgrade the motor at a later date. I do have a blown diff. What I'm wondering is if I should replace the DIFFS with UE ones or go with just the metal cups. The gears inside it are toast so I need the cups and a rebuild kit for the front and rear. Should I just buy the UE's and be done with it or do I save a few dollars and get the upgrades and rebuild kits. I DON"T want to do it again. I'll PAY MORE to have it last it's only going to be a couple dollar difference. Will the Stock shafts work with the UE diffs?

Thanks in advance guys.

Can't really help you there, but I was told that alu cups and case with stock gears should last a while, even under hard BL conditions. Proper shiming is also a good idea.
Those UE diffs are a bit overpriced, IMHO.

Welcome to the forum, btw.

There's just a simillar discusion going on:
http://www.rc-monster.com/forum/show...=&threadid=702

Well thank you :) for the welcome.

If I might ask What do you personaly use and with wich motor do you run?

No, the stock shafts will not work on the ue diffs, they need either MIP or ue cvds (NOT RDlogics/dynamite/GPM etc.). You can get a set of spider gears for 10$, and 2 sets of Fastlane diff cups for 60$. I use these on my lehner 2000XL, and theyre holding up fine (I would imagine my motor is a bit more of a brute than the HV maxx...)

The 6 spider ue diffs go for $220, and a full set of cvds will set you back around $150. If you skud around on ebay, you can probably get a set of used/new ue diffs for $150, and cvd's for under $100......

The choice is yourse. If you do go ue, you shoudl never have any problems with your drivetrain again.

On my E, stock drivetrain on stock motors :P: Never had the bucks to go BL on the E (until I found this place here, but then I was already Revo-lized) :D

And on the Revo just alu cups and a 9L

My concern about the F L diff cups was, I had read a post about some manufacturing process that needed some attention. They (the purchaser) had said he needed to grind the shaft down to get it to fit properly. I wish I knew where the post was. I went looking for it but, I didn't find it. I didn't want to do any modifications to them.

Alright. I have a Feigao 9L and warrior 9920

I run that setup in two e-maxxs. Both e-maxxs are equipped with the FLM Diffs.

Yes you do have to shave the pin. However its a good idea. It makes it so the pin does not spend so no unneccesary ware occurs.

Its a two second job and can be done with a file or a rotarty tool.

Besides now-a-days alot of hop-up parts require slight modding to work.

I'd say get the FLM diffs and you'll be happy! Just remember to lock tight the diff screws!! lol



BTW your running the stock shafts with the HV? Thats crazy I attempted to do the same with my Feigao and litterly did not make it out of the drive way. I twisted them so quick it broke off and flew out of my truck.

heh, that post was me. It was no real problem to sort it out - just a nuisance. http://www.rc-monster.com/forum/show...=&threadid=668

To back up what Rcbros said. An ordinary hand file will NOT work. The spider gear shaft is made of hardened stainless steel, hand files are high carbon steel and are not up to the task. I had to use an aluminium oxide grinding wheel (dremel)

If your still unsure, go with the maximizer ones. They are 20$ more, but don't have this problem.

I try handfile, and rotary out of curiosity. Both worked for me.

maybe my handfiles are just rubbish - they were very cheap, and i emphasize VERY.....

LOL I have no clue what mine are. I just found them in a box of old tools.

@ tomato;

You would be more than fine with the FLM cups, there are more powerfull setups running on those cups with great succes.

The UE's should last forever on your truck though, so it all depends on how much you are willing to invest. The gearing ratio of the UE diffs is different too (stock is 37/13 and the UE's are 43/13) just get an aluminum diffcase and an aluminum diffhousing and some shims to get it meshed perfect, and you should be fine running the 'stock' diffs

When I get a better BL set up will I have to upgrade the diffs then? I only want to do it once. I've already bought a stock emaxx before I realized I should have just bought the parts and made one. Same goes for the HV maxx I should have bought a better setup to begin with.

The HV is a good system for someone just wanting ALITTE BIT more speed and a less mantinence setup.

I would get the 9l and warrior setup.

Steel idlers is almost a most and upgraded diffs would be good as well. CVD's too!

I don't know what your future upgrade plans would look like, but if you want to get a 9L you should be fine.

If you really, really don't like to wrench on your truck, buy the UE's.