1968 M35A2 W/W tranny problem - Steel Soldiers::Military Vehicles Supersite

SEAFIRE · 10-09-2008, 14:08

We had a large grass fire yesterday and 2nd and 3rd gear in our M35A2 W/W stopped working, 1st, 4th, and 5th & Reverse work just fine. We were able to dump the water tank and limp it back to the fire station using the remaining gears and the low/high range.

2 years ago we swapped out the tranny in our other 1968 M35A2 WO/W with no problems, but it didn't have a winch.
We called the Texas Forest Service and they are going to try and find another tranny in the boneyard in Lufkin and get it down to us in a couple of weeks, but it will be without the PTO for the winch.

Question is. we still have the bad tranny we pulled out of the other truck. Can we rob some parts and fix 2nd and 3rd in our existing tranny? It's getting real dry now and with the grass fires starting up again we'd like to get the truck back in service soon if we could.

Or do we need to wait on the other tranny the Forest Service is going to try and find and swap over the PTO when we get it? We've never messed with the PTO yet as our W/W is the first M35 we've ever had with a winch, all the other M35's we've had over the years were all WO/W.
We're lucky to have 2 volunteer firefighters who are diesel mechanics in their "real" jobs, and have kept our fluids topped off and done a lot of work in their free time to keep our M35's running, we've just never messed with the PTO on the tranny before, or taken a tranny apart.

Thanks in advance for any help

Barrman · 10-09-2008, 14:38

You could mix and match parts to make a good one. However, a 2 hour trip to Lufkin is probably easier.

The PTO should swap over. Look in the -20 about installing the PTO and the clearance issues that go along with it. This is a job easier done on the bench instead of under the truck by the way.

jasonjc · 10-09-2008, 14:50

I had one that the keys went and that cewed up the shaft. No replaceing the keys on that one.

SEAFIRE · 10-09-2008, 20:39

Just finished dropping the tranny out. At first we tried removing the top cover and seeing if anything was wrong, we could push the 2nd & 3rd gears in place, and couldn't see anything broke or worn.

We swapped out the top cover with the cover from our "parts" tanny and it still didn't work in 2nd or 3rd, so we backed one of my mechanics service truck up to the truck, put the little crane boom through the passenger doorway, and unbolted and lowered the tranny to the ground.

The tranny & PTO are marked: TMC Wolverhampton England, Tanny is model 3053, PTO is model 4989. One of the rubber boots on the PTO "engage" shaft is split so we'll have to get a new one.

Odd thing, there was a thin gasket between the tranny and the engine, when we did the tranny swap in our other truck there was no gasket? do we need one?

We'll try to tear the tranny down this weekend, this is uncharted territory for us as we've never taken one apart.

gringeltaube · 10-09-2008, 23:20

Quote:

Originally Posted by SEAFIRE

.......
Odd thing, there was a thin gasket between the tranny and the engine, when we did the tranny swap in our other truck there was no gasket? do we need one?

We'll try to tear the tranny down this weekend, this is uncharted territory for us as we've never taken one apart.

I wouldn’t bother with that gasket. Most trannys that I’ve pulled didn’t have one.
Its only interesting if you “plan” lots of deep water fording.
Yes, most probably you’ll find said keys sheared off. Without those the 2nd-3rd synchro hub will spin free on the (motionless) mainshaft. It only takes two ¼”x1”woodruff keys, rather small for their job I think.
How bad is the other tranny? Is it really worth time and effort to swap the PTO? Try to fix this one if it’s a low mileage box.
Just in case, there is enough info on this site if you search for pto+backlash, e.g.

And don't worry, its all simple mechanic and you will find enough helpers here who won’t let you down with this.

G.

DanMartin · 10-09-2008, 23:45

OD Iron has the PTO seal kit...good time to change the boots and seals while it's out of the truck.

DanMartin · 10-09-2008, 23:59

...oh and if you are replacing the studs, make sure you get the same length...even a little longer and you'll never get that PTO off when it's in the truck...it's that tight on the clearance.

SEAFIRE · 10-14-2008, 08:55

Okay,
One of the "keys" came apart, the shaft was messed up, all the gears were good though. Used shaft from "bad" tranny and should have the truck back in service this week.

We discovered the problem with the "bad" tranny was a bad slip ring and a bad 2nd gear. We will be ordering a shaft, seals, and 2nd gear to get the "spare" tranny serviceable.

Thanks for all the help, we've had a crash course in the workings of the model 3053 transmission.

Question? The 3053 is a splicer design, why the "TMC England" markings on the one transmission? did the govt own the design and get the lowest bidders to build them, or was this contracted out? The other 2 we've looked at are marked differently.

gringeltaube · 10-14-2008, 17:05

I guess that at a certain time Turner Manuf. Co. in the UK had been contracted to convert NOS 3052 trannys into 3053s swapping out the 4 parts involved: input shaft & gear (22T -> 29T), its counter-gear (48T->42T) as well as 5th gear (28T->25T) and 5th counter-gear (42T->46T).
I had two of these trannys, rebuilt by TMC. No visible difference to others.

G.

doghead · 10-14-2008, 17:32

At least two of my trucks have TMC transmissions in them. Can you post pictures showing the damaged parts?