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revo trannie problem?

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psychicchuck

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After some bashing with my 10 yr old. I was driving, he was just building the ramp taller and taller etc. Now the the truck will only go forward or backwards for about a foot, foot and a half. took the tranny apart and everthing looked OK. Need some help. Could it be a differential problem?
 
You'd probably hear a grinding noise if it was a diff. Make sure the shift linkage is adjusted right and that the servo is working properly.
 
couldnt say on the diffs so far all of my revo diffs have been fairly bullett proof, but check the u joints in the center driveshafts sometimes the pins come out and get stuck on the chassis plate. The only real problem I've had with the tranny is stripping out the fwd and rvs main drive gears in the bottom of the trans. part #5395x

What is it doing doesit come to a sudden halt or just lose drive power after a foot or so?
 
tranny trouble

No, it shifts clean and full from forward to reverse. fwd a foot back a foot and so on. No weird noises. If you roll it back and forth when its not running you do get a popping or clicking noise then everything locks up. either dirrection doesn't matter.

Yeah it takes of fine for about foot, I took the tranny apart and did'nt see any damage.
 
Then it might be a diff problem try taking off the front driveshaft and try rolling it back and forth if it still locks up then switch it up put the front back on and disconnect the rear then you will know for sure if its a diff problem so you dont have to rip the whole thing apart to dissasemble the diffs if you dont need to
 
tranny problems continue

got to be in the gears, got the spur gear locked up for a bit. are the gears in a t-maxx tranny the same?
 
Main suspect is the diffs.

If you rtun the stock trans, then you do not have a trans diff, which makes diagnosis easier.

An easy way to check the inner diff gears are all ok, is to grab both wheels say at the front and rotate them in opposite directions, if it locks or you feel any rough stopping or grinding, then it is an "internal" diff issue if not then it is good to go. Try the rear end the same, if the inner diff is ok there, then it is most likely a ring gear & pinion problem.

That being the case, drop the front shaft off the trans output and test the rear end, if it rolls ok, then you know it is the front ring gear & pinion. If it locks, then you have found where the issue is.

Hope that helps.
 
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Thanks for all the help. its the front diff. Have'nt taken it apart yet but it locks up with the tranny disconected. I messed up the tranny servo and linkage spring, so now I have to fix that first. Should I just dump the reverse. Is there a kit for forward only?

p.s. I seem to only be psychic when something bad is going to happen. Not really a good thing to be.
 
There is a kit available for forwards only and it IS worth doing.

As to the fron diff, go to traxxas to get the exploded diagram.

To get to the diff, you have to remove the bulkhead (held on by four bolts), then you release the front driveshafts at the diff end, aling the outdrive shafts with the slots on the bulkhead and slide the diff unit out, then to get to the diff, you open the outer diff case which is held together by 2 bolts.

Easier to do than to describe...........

Details for you

TRX-5394X: Forward only conversion kit (eliminates reverse)

Front end exploded diagram

Front End Diagrams (PDF file)

Transmission Exploded Diagram

Tranny E/D (PDF file)


These links download the files to your computer so you will have them as/when needed.

Hope this helps you.
 
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