Motor or transaxle? vibration when coasting

[Fairtax4me]

Got a 98 DS 48v with a weird issue.
There's an occasional rattle/clunk from the rear when accelerating slowly. It's not repetitive, but I can consistently make it happen when transitioning on and off of the accelerator pedal.
Also once the cart is moving above maybe 5mph, there is a vibration from the back when under part throttle or when coasting. Its very slight at lower speeds. When it gets up to full speed it gets pretty severe. If accelerating there is no vibration, it only happens either when coasting, or when at full speed and just maintaining full speed on flat ground. Up-hill or down hill it goes away.
Best I can describe the vibration is it feels just like what you would get from a RWD car or truck with a bad u-joint.

Drained the rear axle oil and it came out clean. Not new, but clean. Put new oil in and it had no change.
All rear leaf spring bushings are new. U-bolts are tight. No odd grinding or whirring noises that would make me think of worn gears or bearings or anything of that nature. Rode around with the rear cover removed and watched the motor/axle for any odd movement and nothing stands out. No externally loose parts that I can see.

I have not yet had time to pull the motor off and check the motor shaft for play.

Just wondering if anyone else has run into this. My google-** is snafu, so haven't really found much when searching. Any idears?
Thanks in advance!

[theboss20]

Had the same problem with my 98 CC DS...turned out to be the rear bearing in the motor. The motor only has one bearing and its in the rear. There is a rubber piece that slides down the motor shaft to cushion the thrust from the motor and I would replace that while you have the motor out. I believe the bearing is a 6202 but can't remember for sure. Replacing the bearing is a pain but doable...the rear bearing retainer screws with two screws from the outside of the rear housing and getting them started and aligned is a challenge. If you decide to do it...I can offer more tips...but one of the most important is to "witness" mark the housing and rear housing before you take it apart so you will get it back together tha same way it came apart.

[Fairtax4me]

Thanks! Kinda what I figured but wasn't sure with the lack of any other strange or obvious noises. If I have time I will pull the motor on Monday and see what I find. Hopefully just a bad bearing and not a chewed up armature shaft.

[93yellowclubcar]

I believe 98 is one of the years with the infamous "nylon guide ring." The symptoms you describe are EXACTLY what happens in a textbook case of guide ring wear. If you pull the motor and see a nylon ring epoxied into the end of the motor output shaft then chances are it is your culprit. It is an easy fix to replace this part also.

[Fairtax4me]

Well, got the motor out today.
No guide ring... And no bad bearing.

Found the spline end of the armature shaft was pretty worn, and the input spline into the transaxle is severely worn. Not even sure what happened because it looks like someone took a grinder to it. But if you could see the redneck engineering on some of the other carts... its no real surprise.
I have a spare axle here that I'm gonna pop in the cart for the time being and hope its any good. It sat outside for a really long time so I have no idea what condition its in internally. Guess I'll find out!
I'll split this axle at some point when I have time and try to pop a new input shaft into it.

Thanks for the tips!

[93yellowclubcar]

Man, sorry to hear it wasn't as simple as a guide ring. At least you have a spare axle handy, that's better than being totally down while ordering parts. Another tip: smear some anti-seize on the input shaft before putting the motor on, down the road if it has to come back off you'll be happy you did.

[Fairtax4me]

Swapped the axle and it seems alright. Might be a little bit of whine from the axle but not bad. Something about the brakes on the "new" axle was different though because I let it down off the jack stands and backed out of the shop to test drive it and the brake pedal went right to the floor and had no brakes at all. O.o

Had to make an adjustment up at the front of the cables to get the pedal right. After that all was smooth. Also found that someone had rigged up two pedal return springs on it for some reason. Took the second one off. Seems fine to me with just one! Stops fine and the pedal comes back up to where its supposed to just fine. On to the next one!