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Wijames's avatar
Wijames
Explorer
Mar 04, 2015

Transmission acting up?

I just purchased a used 1994 Thor Chateau 28 foot class c motorhome and noticed that the transmission shifts smoothly but won't shift till I let off the gas. It has a ford 460 engine . Any thoughts as to what could be the problem?

Thanks
  • Sounds like your C6 trany is acting up.
    Have it checked and adjusted (or repaired), then add a Banks Trans-Command module. It firms up the shifts and lowers over-heating under load issues.
  • If it's truly a C6 then I would get under it and make sure the small vacuum line hose is still connected to the modulator. It's on the left rear of the body of the trans.
    If this hose comes off (and they often did) the trans thinks you have the accelerator on the floor.
  • I agree... Faulty vacuum modulator... Replace it... Then check vacuum line at module and to lines under hood. Follow the line. May have vacuum leak with dry rotted hoses...
  • I would have it flushed and serviced and have them check the lines. Personally i would bypass purchasing the banks and spend the money on a quality rebuild.

    Stay away from the chain tranny rebuilders. They replace ONLY what is worn at the time then guarantee it hoping to never see you again. Records on one of my

    trucks showed three visits to Aamco for problems after a rebuild. I had it pulled by an independent shop and it went another 175K miles with no problems.

    You decide.
  • n7bsn wrote:
    Sounds like your C6 trany is acting up.
    Have it checked and adjusted (or repaired), then add a Banks Trans-Command module. It firms up the shifts and lowers over-heating under load issues.

    I found out this morning that I have an early model E40D transmission with overdrive. My friend (Who works on transmissions) said it has had several updates available to the electronics and has probably not had any of them done. Unfortunately, he doesn't have a lift outside so he cant work on it for me.He said it was very complex. Has anyone had any experience with these?
  • Do a code scan first and see what you get.

    There is no upgrade AFAIK electrically..

    It sounds like your intermediate clutch pack has worn out. It is barely gripping, and cannot engage under load, but once the load decreases it can engage.

    It is easier for the clutch pack to hold than it is for it to engage initially so this is a common first sign of problems. It is also possible that to get this feeling from an E4OD that is skipping second gear completely and going to third due to a worn clutch pack or a damaged intermediate one way clutch.

    It will stay in first for the entire time it should be in second, and then go immediately to third. See how many shifts you get after the first gear change to determine whether or not this is the problem.
  • lawrosa wrote:
    Do a code scan first and see what you get.

    There is no upgrade AFAIK electrically..

    It sounds like your intermediate clutch pack has worn out. It is barely gripping, and cannot engage under load, but once the load decreases it can engage.

    It is easier for the clutch pack to hold than it is for it to engage initially so this is a common first sign of problems. It is also possible that to get this feeling from an E4OD that is skipping second gear completely and going to third due to a worn clutch pack or a damaged intermediate one way clutch.

    It will stay in first for the entire time it should be in second, and then go immediately to third. See how many shifts you get after the first gear change to determine whether or not this is the problem.

    It's really kind of strange, I'm starting the problem is from the motorhome not being used for a long time because the more I drive it, the better it shifts. I am feeling four shifts now and it's shifting on its own. I'm going to have it checked out but it's doing much better.
  • My 95 Dodge diesel Scotty MH had 50,000 miles. It had pulled a enclose car trailer all its life. I desided to have the transmission bullet proof so I had it done with a 3 stage torque converter, special valve body and all steel parts. What a difference it felt that I got 150 horse power more and I am sure happy. cost 3,000 bucks but worth it. I don't half to worry now about the tranny. Don't take short cuts in rebuilding the tranny.