noise on acceleration

[jpfarmer13]

Let me start off by saying im very new to rc. I bought my first rc a mini summit 2 weeks ago. I have been an auto tech. for 16 years so im pretty good at diagnosing vehicle problems (at least on full size vehicles). I have a rotational cracking noise in the rear on hard acceleration. Only when I go forward, no prob in reverse. Ive checked all my axles, driveshafts and the rear diff. No obvious problems. I did notice when reassembling the rear bulkhead that the plastic flexes when you tighten the 1 screw that hold the entire thing together pulling the far side apart if you over tighten it. I think the bulkhead may be flexing letting the rear gear momentarily loosing contact with the pinion gear causing my noise but im not sure. ANY help would be greatly appreciated. thanks

[jpfarmer13]

ok ....after a lot of looking around it seems i need to shim my diff. Where do i get shims??? From Traxxas???? Also Im thinking of getting metal bulkheads any suggestions???? I would prefer quality over cost, so far ive only found integy bulkheads. Are they any good? Are they the best??? what other options do I have???

[revomaxx2223]

I think traxxas makes a diff rebuild kit with shims.

[Jimmie Neutron]

Traxxas does sell replacement parts... but they do not have a kit with shims for this platform that I know of.
Part 7079 is what I believe you need...

Also check out this (entire) thread:
http://traxxas.com/forums/showthread...-your-bulkhead

[jpfarmer13]

thanks for the thread link jimmie.... LOTS of info!!!!! any suggestions on new/good bulkheads??? This seems to be a very common prob. right outta the box (mine went 3 battery charges befor it got noisey) Youd think traxxas would make better/more solid bulkheads that fit properly...

[Jimmie Neutron]

I am running (original) stock bulkheads and have not had any issues; even with 3S and a 4370Kv motor.
A properly shimmed bulkhead (which may need reshimmed after a few runs with new parts) will hold up pretty well.

But if you want alloy... pretty much all of them have proven to be worthy.
HR's are a little nicer due to the multiple screws to hold the halves together.

[jpfarmer13]

The multiple screw/fasteners sounds like what im lookin for. 1 screw just seems like it leaves the other end open to possible spreading. Id like it to be nice and secure... im kinda rough on my toys... But being rough is half the fun. Where might I try looking to find the HR brand? so far ive only been able to find integy.

[Jimmie Neutron]

Toyz... eBay... maybe others.

[jpfarmer13]

found them.....80 bucks each. OUCH!!!! I hope they are worth it...

[Jimmie Neutron]

Keep in mind that the screw holds one end of the bulkhead while the blue aluminum tie bar holds the other.
So... a cheaper set like GPM or (dare I say) Integy might work just fine.

[jpfarmer13]

Jimmie you seem to know what you are talking about, can u take a look at one of my other threads......"Integy parts whats the deal" and give me your opinion when you get a chance please. Thanks

[Jimmie Neutron]

This post stated everything I was going to say... so I decided not to clutter up the thread:
http://traxxas.com/forums/showthread...=1#post5217471