Totally Tight Traxxas

Question:
Hey Doc-
So I have a Traxxas Slash 4WD that was built by a renowned racer. But now the drivetrain seems really tight and will not roll freely. What should I tear into first to resolve this issue?

Thanks
Ryan

Answer:
Hey Ryan.
Well, since this truck was built by a ‘renowned racer’, I’m sure it’s in perfect working condition!

My first suggestion would be to see what part of the car seems tight. Since it’s 4WD, you have quite a few areas that could be affected; front wheels, rear wheels or the central drivetrain. Thankfully, the Slash 4×4 is somewhat modular to help us out too.

Let’s do some step-by-step analysis:

1) Start by loosening the motor and rotating it away so that the pinion is not in contact with the spur. Once that’s done, give the drivetrain a good spin. If it spins fairly easy, the problem might be your motor. Remove the motor from the car. Turn on your transmitter and Slash and, while holding the motor in your hand, gently give ti throttle. If it seems sluggish, you might have a bad motor. Be careful, though, as the spinning pinion can chew up fingers!

2) If the drivetrain felt bound up, remove either the from or rear clip from the truck. The rear might be easier since the front has the steering links tying it to the chassis.

3) Once removed, spin the rear tires. If they spin freely, move to step 4. If not, my guess would be a blown bearing. The rear differential is pretty durable and not normally a faulty part. Start by removing each tire and checking the rear hub bearings. If they look good, move to the differential and input shaft bearings.

4) If the rear seems ok, spin the front tires and check how free they spin. If they don’t, you could have a bad bearing in the front somewhere. Start by removing each tire and checking the bearings. If they look good, move to the differential and input shaft bearings.

5) If all the bearings look good, the problem may be a bit deeper. With the Slash still apart, check all the plastic where the bearings sit. Heat can cause alot of damage to plastic, and if the bearings got to hot they could have easily melted a portion of the plastic, causing the alignment of the driveshafts to be skewed. This would certainly cause a bind in the drivetrain.

Remember, if the truck is still under warranty you can give Traxxas a call. They have excellent customer service and I’m sure will be able to help you out.
The Doc