transmission issues

[bootdoc]

I'm looking at a 79 revcon. The ad said the transmission had been recently rebuilt. I took it for a test drive and while on the highway it dropped out of 3rd gear at about 55 and stopped accelerating.
I pulled to the side of the road and shifted to 2. It moved moved forward fine. As I gained speed I shifted to D with no noticeable difference. Sounded like it was still in 2. I shifted between D and 2 several times as I drove it back to the sellers house. I could not hear or feel a change in gear. The owner sent text today saying it was a seal. Am I looking at possibly rebuilding the transmission? Is the seller not being honest?

[Mike_Hohnstein]

Transmission is a T-425 Hydramatic. Passing gear or detent down shift is electrically controlled, if the detent solenoid is weak or defective it can cause upshift issues. Sticky down shift switch on the throttle linkage can do the same.
If it's not detent control issues the problem is deep, and finding a good shop that could do efficient service work would probably be a challenge and beyond the value of the vehicle, as stated previously.

[2324delk]

My son has a Revcon, his was slipping. It turned out being a hard line leaking.

He fixed it himself.

[egh33]

Watch your RPM's that should give you a clue if it's shifting or not.

[turbojimmy]

wolfe10 wrote:
Yes, Revcon's are front wheel drive. Depending on year, it could be the Toronado transaxle or if later model after the full size Toronado was discontinues could be another brand of FWD transaxle-- not positive, but remember ZF as the brand.

In that case I respectfully withdraw my comments that they're easy to get out 🙂 I have no experience with the Toronado drivetrain (though I have tortured myself with removing the transaxles from several FWD vehicles).

I still wouldn't hesitate to do it myself, though I suspect it has to be more complicated than a RWD. The sale price has to reflect that risk, which as someone else pointed out renders the thing pretty much worthless.

[wolfe10]

Yes, Revcon's are front wheel drive. Depending on year, it could be the Toronado transaxle or if later model after the full size Toronado was discontinues could be another brand of FWD transaxle-- not positive, but remember ZF as the brand.

[whem2fish]

is this not front wheel drive most were olds. a member Dave has one with a 502

[427435]

It may be a bad seal------------but the seal is likely in a clutch pack inside the transmission. That means a transmission removal and disassemble. If it was recently rebuilt, why doesn't the seller have the rebuilder fix it?

[olfarmer]

If you are willing and able to fix it yourself and can get a super buy on it then go for it, but paying someone to sell and install a rebuilt tranny will cost more than the unit is worth. Also, I question the owners diagnosis of a bad seal. Good Luck!

[the_silverback]

Move on!!

[redguard]

Installing a properly rebuilt trans in a 79 Rv will cost as much as the unit is worth

[doxiemom11]

There are many men who are very capable and would be able to purchase a rebuilt transmission and intall it themselves. All things are not fixed by shops as many of you do it your selfers should know. See what documentation he has, and then decide based on that if you are still interested, wish to have a transmission shop check it, or walk away.

[352]

Ask him for the build sheet. If he can't produce this from the people that rebuilt it then it didn't happen. Move on.

[tropical36]

Mandalay Parr wrote:
Tell him you will consider After He gets the tranny repaired.

He most likely won't do that unless he's sure of the sale, so it might be best to use it as a tool to negotiate further, using a little more than the price of a rebuild. Then install a good used one instead and after all, the rest of the rig is used.

[turbojimmy]

"Recently rebuilt" could mean he attempted some kind of repair on the trans to get the thing out of his hands. A recently rebuilt trans, if rebuilt by a reputable shop will look brand new.

The diagnosis of "a seal" is suspect. What you describe sounds like a loss in pressure so it won't hold 3rd gear. While this could be one of a variety of "seals", you'd need to remove the transmission to properly diagnose and repair it. I think you're looking at trouble unless he can produce a receipt for the repair or the rebuild.

BUT, if you're handy I wouldn't be afraid of swapping out a transmission in these old things. Everything is easy to get at, but I'd knock $1k off the asking price for the risk. I'd guess that you can find a good, used trans on CL for that much. Or, $1k would get you half way to a proper rebuild.