Discussion:
Clark Transmission Removal C500-50

Hi, I have recently purchased a forklift that unfortunately has a slipping transmission. It also has no brakes.

Clark C500-50
Lifting Capacity 4450 pounds
Year: it looks like 1970, not 100 percent sure

The truck only moves when you rev it high, full throttle and then it moves forward or backward. If you let loose of the accelerator, you have to start all over again. I control movement using the inching (left) pedal. So it seems like the clutch packs are worn. I can also hear a knocking/ticking noise out front of the transmission around the dipstick once its warmed up.

The oil is pink, like a strawberry milkshake, so it seems like coolant entered through the radiator. The inching valve and parking brake works, the torque convertor functions well. I haven't yet pulled the wheel to check the brake shoes, the reservoir was low on oil however.

I know I'll need to replace the transmission. I couldn't find any procedures or manuals online on how to do so. Has anyone done this before? Do you need to first remove the mast or can you get away without removing it?

I am an automotive service technician, so this is a learning experience for me, more than just the technical piece. Regret the purchase, but stuck with the lift now.

Thank you for reading!
  • Posted 7 Aug 2020 03:52
  • Modified 7 Aug 2020 03:56 by poster
  • By RPAUTO
  • joined 7 Aug'20 - 4 messages
  • Ontario, Canada
Showing items 1 - 4 of 4 results.
Hi stillworkin, I have worked on these trucks for many years, you will need to remove the mast to remove the transmission, however the mast removal is not so bad. You said the oil in the transmission was not burnt so I would suggest you look at the dump valve on the transmission control cover first, this has a small cup seal in it that sometimes swells and causes the valve to stick and can give the problem you have. It is easy to change the seal so worth checking this first.
Hope this helps.
  • Posted 25 Jan 2021 10:51
  • By ROCK
  • joined 25 Jan'21 - 4 messages
  • Ireland
If trans oil low you should first add 1 gallon and see if problem goes away ATF dextron
  • Posted 14 Aug 2020 01:24
  • Modified 14 Aug 2020 01:39 by poster
  • By stillworkin
  • joined 2 Nov'18 - 96 messages
  • New York, United States
Thank you!
  • Posted 11 Aug 2020 00:12
  • By RPAUTO
  • joined 7 Aug'20 - 4 messages
  • Ontario, Canada
Well you have a job ahead of you sir. The upright needs to be removed along with the dash cowl and seat deck for easier access.
The brakes are inside the diff housing. If you are pulling the transmission, you can leave the axle ends with the brakes on until you get it on the floor or work table but I always took the axle ends out before pulling the transmission to reduce the weight and bulk.

You will need to find a manual for sure. I cant supply it but you should be able get a service/overhaul manual from your Local Clark dealer for a reasonable fee.

Good luck!
  • Posted 7 Aug 2020 06:35
  • By kelsey
  • joined 24 Aug'08 - 24 messages
  • Tennessee, United States

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