M35A3 won't shift out of first gear in Drive

[HDN]

I'm looking at purchasing an M35A3. It's been sitting for about ten years, but it starts right up and everything works, except the transmission won't shift out of first gear in the drive position. Doesn't matter if I'm in high or low range. Run the engine up to 2500 rpm and it just doesn't want to get out of first gear.

I checked the oil level for the tranny and it's good, but the tranny oil filter hasn't been checked. Maybe it's clogged and causing problems?

The truck can go in reverse just fine. The gas pedal is a bit sticky though, but I heard the throttle cable sheath gets gunky with lack of use.

Any thoughts?

 

[glcaines]

How far have you driven it in 1st gear? You may want to drive it a fair distance in 1st until the transmission is thoroughly warmed up, but be careful not to overspeed it. I'm assuming that it still has motor oil in the transmission? Mine used to delay shifting up and especially down when I had motor oil in it. I switched to Dexron 3 and the transmission shifts much smoother. If you purchase the A3, I would recommend switching to Dexron 3. As for the accelerator pedal, mine seized up on the pin where it pivots at the bottom due to corrosion. I tried fixing it, but ended up replacing it with an NOS pedal from Ebay for ~$5.00. The pedal is identical to an M35A2 pedal. That transmission was designed for Dexron 3. If you do change to Dexron 3, you need to make absolutely certain that all of the motor oil is gone as Dexron 3 is not compatible with motor oil. I did repeated drain and fills with Dexron 3, driving miles and shifting up and down to make the change. I used NAPA brand Dexron 3 equivalent which is made by and equivalent to Valvolene Dexron 3.

 

[HDN]

Yes, I forgot to mention the tranny still has motor oil in it.

I couldn't find transmission shift points in the manuals that I have for the truck. Are these points published anywhere?

 

[HDN]

I'm giving this a little bump. I plan to troubleshoot this with the seller this Saturday. He wants a working tranny as much as I do!

Another detail is that we've only driven the truck off road in a field. Is this mechanical automatic transmission smart enough to adjust its shift points based on rolling resistance?

 

[cattlerepairman]

Your mileage may vary but I would buy this truck as-is, neglected for 10 years, not serviced and with a dead tranny, essentially undriveable, and make my offer to the seller accordingly (a tranny rebuild is an easy 5k if you have to outsource it). Then I would get the truck home and THEN I would trouble shoot. If it turns out to be an easy fix - good for you. You still had to do the research and the leg work.

If it isn't a quick fix and you need a tranny rebuild (note that there is quite some wisdom on this side on kits to use and making the clutch packs stronger etc.) at least you planned for it and saved that money up front on the purchase.

What good will come from trying to troubleshoot with the seller prior to purchase? If the tranny magically shifts right on the next test drive, are you going to pay full fare because you trust that this is now a fully functional truck?
Of course, if you do that, you take the full risk if the tranny completely dies after you get the truck home. The seller will still be happy, you bought as-is, but will you be?

If the seller wants top dollar for the truck, he better service it, repair what's broken and then offer it for sale. An engine that has been sitting for ten years needs an oil and filter change before is even started. Why pump old, acidified, oxydized oil potentially full of cr*p through the whole engine? I digress.

Not wishing to rain on your parade, and it is totally your money.

 

[rustystud]

Your mileage may vary but I would buy this truck as-is, neglected for 10 years, not serviced and with a dead tranny, essentially undriveable, and make my offer to the seller accordingly (a tranny rebuild is an easy 5k if you have to outsource it). Then I would get the truck home and THEN I would trouble shoot. If it turns out to be an easy fix - good for you. You still had to do the research and the leg work.

If it isn't a quick fix and you need a tranny rebuild (note that there is quite some wisdom on this side on kits to use and making the clutch packs stronger etc.) at least you planned for it and saved that money up front on the purchase.

What good will come from trying to troubleshoot with the seller prior to purchase? If the tranny magically shifts right on the next test drive, are you going to pay full fare because you trust that this is now a fully functional truck?
Of course, if you do that, you take the full risk if the tranny completely dies after you get the truck home. The seller will still be happy, you bought as-is, but will you be?

If the seller wants top dollar for the truck, he better service it, repair what's broken and then offer it for sale. An engine that has been sitting for ten years needs an oil and filter change before is even started. Why pump old, acidified, oxydized oil potentially full of cr*p through the whole engine? I digress.

Not wishing to rain on your parade, and it is totally your money.

This is great advice from cattlerepairman. I would listen to it.
I was going to give you the information after you bought the truck. No need to increase the value before you buy it !

 

[cucvmule]

After you trouble shoot and possibly repair for the seller, the seller may just decide to keep truck.

Just Saying

 

[Valley Rock]

I'm giving this a little bump. I plan to troubleshoot this with the seller this Saturday. He wants a working tranny as much as I do!

Oh I'm sure he does, truck is worth a lot more that way .

Trouble shooting this with the seller is the last thing I'd do personally, truck has issues, possibly very expensive issues in the eyes of both the seller and buyer, I would buy it on the cheap and drag it home then ask my friends to help me fix it .


But that's just me .

 

[HDN]

I agree with everything being said here. What I didn't say is that the seller is a family friend, so there's more than money in this sale.

 

[HDN]

Here's an update: The owner and I took it on a test drive on pavement for the first time, and it shifts! However, it has high shift points. It didn't seem to want to shift until 3000 RPM! But I kinda wonder if the tach is out of adjustment.

Another thing that seemed to compound the issue was the sticky gas pedal. Yanking it back quick with my foot told the tranny to upshift. After some finagling with the gas pedal, we got to fourth gear at lower RPM.

After we parked it, we lived up the gas pedal hinge and the throttle cable sheath and it freed up, properly springing back to a 800 RPM idle. The return spring seems pretty dinky! I thought the cable needed some slack adjustment, but with the pedal properly returning to idle, it seems like a non-issue.

So did I buy the truck? Yes, I did. And I'll save that for another thread.