Technical Question for the transmission gurus

I put my Tudor on the road and it doesn't shift right.
It goes ok from 1st to second, but it feels like it goes back to 1st instead of 3rd. I changed the modulator, but no change. It's a 350 with a turbo 350.

Am I looking at a rebuild, or is something out of adjustment?

Thanks

 

There is not much to adjust on those. The kickdown cable, and shifter linkage.

Is it an old used transmission? do you know the history of it?

Mostly, old used TH350s need to be rebuilt. But make sure the fluid level is correct first.

 

It was in the car when I bought it. Supposedly a driver.

No kickdown, but I don't see provisions for one.

 

i wonder if a stuck governor could cause that?

 

It's possible, although it's a bit more likely that the gov gear broke off, or is stripped. Ford and Mopars with the gov on the output shaft seem more likely to stick. Will it shift if you let it rev up pretty high?

The kickdown cable attaches near the dipstick tube. Sometimes it gets left off, etc.

 

It shouldn't go back to first, after accelerating through second.. It would feel like you were going through the windshield. Most likely, the direct (3rd) clutch is toast, and it drops out. Intermediate clutch is off, so all you have is the forward clutch working, momentarily
Put it in reverse, and try up back up an incline.See if it holds.
What does the fluid, filter look like?

 

I drove my 51 Merc for years with an Olds 350 R and turbo 350 with no kick down cable. The biggest issue of not having one that I see is that the trans wants to shift from first to second real quick. That may be the issue, it may be going into second so quick you don't notice it and think you are still in first.
Plus it obviously doesn't kick down when you pull out to pass at about 50 and need it to.

 

Fluid is clean. Haven't checked filter. Haven't gone over 25mph.

Will pull the governor tomorrow.

Thanks

 

I doubt it's the governor. If it opens consistently on the 1-2 , I wouldn't think it would not want to open for 2-3.
but, check the driven gear, and clean it good with carb spray. Then hold the weights closed and turn it over and make sure the valve inside moves freely.

 

Put the rear up on stands and shift it manually and then see if it shifts automatically. Sounds like governor problem . TH 350's are easy to rebuild. Any transmission shop will do a bench job fairly cheap if you pull it and clean the outside of the case . The kickdown will be a cable right by the fill tube on pass. side of the trans. The filters on those will plug up and restrict flow. I bought a 69 Impala once that had been driven from California to the Grand Canyon and stopped working. I changed the filter and fluid and put a shot glass full of brake fluid and had a running driving car .

 

....but it still needed the transmission rebuilt, most likely

 

Just thinking about this earlier.
I'd probably road test it. Start out in manual low, part throttle , shift to second, then shift to 3rd @ about 40 mph.
Keep foot at part throttle. That will tell you if you have a direct clutch.

 

Squirrel, you are probably right ,but 2 years and about 10,000 miles later when I sold the car that transmission was still in the car.

 

They will often keep working for quite a while, with pretty bad innards.

 

Governor was stuck. Cleaned it and made no difference.

Sounds like I'll be needing a rebuild.

Thanks for all the input.

 

That is what you need to do normally a governor will not cause the no 2-3 shift. It sounds like an internal problem.

 

Yes. Strange that it would work for 1-2 shift.
If you've got metal and /or friction debris in the governor, it's time for a rebuild.
Get yourself a good book and a few simple tools .The T350 is one of the easier transmissions out there.

 

Turbo 350s and 400s will do strange things if the vacuum modulator is hooked up to ported vacuum. They will shift to 2nd but when they would normally go to third, they may feel like they went back a gear or started slipping due to the intermediate roller clutch overrunning.
Make sure the vacuum modulator is hooked up to manifold vacuum.
Bill

 

That is a good point. The o/p was questioning a rebuild so one would assume the vehicle has been on the road and was hooked up properly, but he does say he'd put it on the road. So maybe it is a used trans in a new vehicle. In that case yes. Check the vacuum source.

 

If the 350 is anything like a C4, then there are two clutch paks. One is the forward clutch, which is used in DR for all three gears. The other is the Reverse/High clutch, which is applied in Reverse, and when in 3rd gear. As was noted, try reverse. If it works correctly, then the reverse/high clutch might be alright.
It does sound like the reverse high clutch may be going, because it will slip on initial apply of 3rd gear and engine will rev up.

 

turbo 350 has intermediate clutches. The band is for engine braking only. But still you are right that the direct clutch could be failing. That's why I suggested trying reverse earlier. Direct clutches and low reverse in the back of the case make reverse gear.

 

25 mph? Maybe you need to try at a speed limit, maybe it will go into high gear?


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