Motor Home Transmission

[gunner]

I have been experiencing for several years a transmission problem and I am contemplating if I should get it repaired. The problem is when it is cold 30 degrees F or less the transmission when cold ( motorhome sat overnight) will slip until the engine runs for a couple of minutes. During the summer or warm weather there are no problems with slippage and you can put it in gear and take off as soon as you start the engine after not having been run all night. I was told that the seals in the transmission are probably at fault and having shrunk. They swell to the proper size when warm. Has anyone else experienced this problem and what did you do to correct it.

[cooperhawk]

I was having similar problems with my Explorer transmission and figured what did I have to lose, so I put in a can of Sea Foam conditioner and it works fine now. Sea Foam claims they soften seals and such. What the heck, cheaper than a tranny rebuild and if it doesn't work, then you still get the rebuild.

[bobchevy89]

Hello
have you had the trans serviced? new fluids and filters.. If it keeps slipping it will burn up the tranny real fast. and most likly it will happen when you are miles from home.

[Poprivet]

In some ways, you are lucky - the transmission is telling you it's worn out and in the not to far future is going to fail. As with engines, a factory rebuilt replacement is, in my opinion, the only way to go. Automatic transmissions are fairly complicated and have several critical clearances and set points. As a complete unit, simple to replace. Good luck!

[Robfike]

Gunner,
I had a full size Buick that did the same thing. I thought I had plenty of time to get the trans overhauled, but it burned up on the interstate one day with an outside temperature of below freezing.
When we got our 345, the trans was leaking fairly badly on the ground. There is a transmission shop here in Indy that I have had good luck with, so I had them overhaul our trans. That has been 15 months ago and 9000 miles. Works great.
Good luck, Rob

[gunner]

Had the fluid and filter changed, dropped the pan to do it did not have it flushed. Did not find any metal shavings or anything else in the pan other than fluid. When I purchased the unit in Alabama over Thanksgiving over five years ago I had no problems with the transmission because it was warm when I started and drove straight through to Ohio. Even then when it sat overnight during the winter it would slip. Mechanics have told me that basically the seals will swell and not to worry about it but like everyone else I don't want to get stuck on the road.

[gunner]

Rob can you provide an estimate cost for having the transmission pulled and rebuilt? What kind of warranty did you receive with the rebuild.

[bobchevy89]

Hi gunner what you described is front pump leaking inside , when it goes 1st and reverse are lost. 1 giant netrual. been there done that on my chevy pickup.
Bob

[Robfike]

Gunner,
I believe the whole job was right at $1200. Their warranty is 12 months or 12,000 miles. This is the third transmission I have had them do for me. All have been great.
Rob

[RUSSELL]

To me it sounds as a torque converter drain back. The reason it take for few seconds before it starts moving is that your torque converter refils. Normaly the problem is the front bushing or the hub on the torque converter is worn out. Is your trans a hydro 400 3 speed? If your seals and o rings get hard they will also act the same way. It is a common problem for Ford.Chev. does not normaly do this, unless it is over 10 years old. The best way is to take the motorhome to a trans shop and leave it overnight so they can check it out cold.
Regards from Russell in sunny Tucson Az.

[gunner]

Thanks for everyone's input. I am having a automotive garage giving me an estimate of either rebuilding my transmission or replacing it with a rebuilt one from Jasper.

[Poprivet]

Jasper - JASPER - JASPER!!

Good luck with whatever you decide - It's possible I could be slightly opinionated. But I doubt it.

[Chaplain Kent]

What's the possibility of putting in a four speed or an overdrive transmission? I am still in the market to lower my RPM and increase speed.

[GlenCoombe]

Kent's right. Now's the time to explore changing up to a newer 4 spd tranny. If you're going to go to a Jasper replacement why not go to an early 4spd without the computer stuff? I'm assuming the next version of the TH400 didn't need the computer and still shifted off vaccum.
So will the crowd now please educate us on what we would need to do... I'm sure the steering column would have to change for the 4spd unless a remote shifter leaver was used.

[Poprivet]

Originally Posted by GlenCoombe

Kent's right. Now's the time to explore changing up to a newer 4 spd tranny. If you're going to go to a Jasper replacement why not go to an early 4spd without the computer stuff? I'm assuming the next version of the TH400 didn't need the computer and still shifted off vaccum.
So will the crowd now please educate us on what we would need to do... I'm sure the steering column would have to change for the 4spd unless a remote shifter leaver was used.

I don't know as I agree. A four speed would certainly be a nice upgrade but I think you need to consider the cost verses how you plan on using the moho. If you plan on 15 to 25k miles per year then yup, might be a smart thing to do. But, if your down in the 5 - 8k range, maybe not. If you travel in mostly mountainous Terran, no maybe about it, the 3 speed is cool. If you drive 50-60 mph, the 3 speed is cool, If you toe something, the three speed is cool. Of course, you could always go with a Duramax and an a Allison 5 speed.

[JKWoodrow]

Originally Posted by gunner

I have been experiencing for several years a transmission problem and I am contemplating if I should get it repaired. The problem is when it is cold 30 degrees F or less the transmission when cold ( motorhome sat overnight) will slip until the engine runs for a couple of minutes. During the summer or warm weather there are no problems with slippage and you can put it in gear and take off as soon as you start the engine after not having been run all night. I was told that the seals in the transmission are probably at fault and having shrunk. They swell to the proper size when warm. Has anyone else experienced this problem and what did you do to correct it.

Gunner:

I have encountered the same situation several times and have had great luck in following this advice from my good friend who is a professional transmission guy: 1) have the transmission power flushed which exchanges all of the fluid (about 16 quarts). 2) install a new filter. 3) add a can of Lubegaurd Red, Lucas or Seafoam transmission juice. 4) Drive it.
I recently resurrected a very troubled transmission in a 370 this way. After the treatment, we drove it on a 1500 mile trip with absolutly no trouble.

[Howard Lefkowitz]

Originally Posted by Chaplain Kent

What's the possibility of putting in a four speed or an overdrive transmission? I am still in the market to lower my RPM and increase speed.

You can have a six speed with overdrive by adding a gear vendors. I put one in my 1990 16 years ago and it still works fine.

[Mike Lewis]

YOU MY NOT HAVE TRANS PROBLEMS !!!!! Don't rush into a trans replacement or over haul. I have rebuilt a bounch of these over the years and symptoms here don't add up. Converter drain back:--it is just as likly to drain back when it's warm as when it's cold. No metal or matterial in trans pan: When ever slippage occurs clutch plate matterial nearly always is found.
My guess from afar: I would suspect the engine FAN CLUTCH. When they begin to fail many times they won't release and run engine speed and make noise much like an airplane prop. This can and is, many times, mistaken for a slipping trans. I personally overhauled a trans for this reason only to find the vehicle had a fan cutch that was frozen up.----pieman

[Chaplain Kent]

Originally Posted by Howard Lefkowitz

You can have a six speed with overdrive by adding a gear vendors. I put one in my 1990 16 years ago and it still works fine.

I talked with Gear Vendors and it is not available for my diesel engine.

[M Hohnstein]

Originally Posted by Chaplain Kent

I talked with Gear Vendors and it is not available for my diesel engine.

I have applied GearVendors to several vehicles, it depends on the transmission type in the vehicle. Import transmissions are out of luck, but domestic rear drives, ie T 400, C-6 and Torque Flight are covered.
The cost and complexity of updating to newer OD type transmissions is prohibitive on a vintage MH, unless money is no object.
A point of reference, a 4L80 OD will bolt to the 454 or GM diesel but it requires a stand alone computer to control it. A very good price on such a project would be around $4000, I think one could buy a lot of fuel for the exta money. The key to living with the old 3 speed is drive slow and keep the RPMs under 3000 in gassers, 2500 in diesels.