1939 D-35 Engine and Trans

I have a few questions for you guys that you may be able to help me answer.

1. From the pictures posted, what is the actual size of engine in my truck?

2. What is the model of 5 speed transmission

3. Can rebuild kits be bought for this stlye of transmission? Or would parts such as bearings and seals have to bought seperately.

4. Could a later model sync. transmission be bolted up to this engine? If so what does it totally involve?

This truck was given to me by my father and spent a good portion of its life in cold storage. The engine runs amazing and only has about 10,000 miles on it. My father and me droped the oil pan on it a few years back and the bottom end was perfectly clean. The hone marks are still visible on the bottom of the cylinders.

As far as the engine everything thing seems to check out alright, however the transmission is somewhat of a issue.

I took the old girl out for a drive and everthing seemed great until I found out it wouldn't shift into 5th gear. I ended up popping open the transmission to find a good portion of rust. With a good flush out of diesel fuel and a can of PB blaster I was able to get the everything loosened up nicely. Unfortunately, "what I believe is part of first gear, see manuel pic." is way beyond surface rust. I would say about 15 teeth on that gear are heavely rust pitted.

I took the truck out for a drive and I didnt hear any odd noises ,but I cant help to think that in the long term that paticular gear might cause damage to its mating gear underneath.

I assume the bearings are still alright, but to be honest I would rather take the transmission apart and repair it in a proper manner or find a suitible replacement.

Has anyone ever replaced one of these non sync. transmissions with a later model sync. trans. with minimal machining????? Thought I would throw out the ideal of it for conversation.

I thank all of you for your time and effort in helping me shed some light on this situation.

Brent

Here are some more pics!

And more pics!

You say the engine only has 10K?
If the heavy pitting on the trans gear is first gear and you don't hear noises I say fill it back up with gear oil and drive it. You only spend a short time in first.
Yes, many of us are looking to try a later model trans with synchros.
There's a T-98 IHC trans that came in later IHC trucks that has been successfully transplanted into K series trucks. (1940-49)
I don't know if this will work for you.
Certainly it will take some modifications. You have to modify driveshaft as well.
I've never seen a kit for these transmission rebuilds.
If you rebuild it, you disassemble it, clean the parts and then order the bearing or seal you need.
Those parts are most likely available.
"Hard parts" like gears are a completely different matter. This stuff has been obsolete for decades.
If I were faced with that situation I'd either be looking for another stock trans ( around here there are 5 D-30s for every D-35 and not many D-30s)
Keep in mind that at 10k mileage yours will be much better probably overall then what you're looking at!
Or to retrofit a newer style synchro truck trans like the T-98??
That little rusty gear on your trans is looking more and more minor...
I and other folks on this site have D-30 and later transsmissions. D-30s had flathead engines. I don't know if a D-30 trans will fit. Trying to find another D-35 trans might be hard.
I guess it depends in the end how handy you are wih this stuff.
People are retrofiiting old car and trucks everyday with 700r4 GM autos and S-10 5 speed manual trans.
There's no " kit" for this on your truck, it's too unusual.
You'd have to make your own adaptors.

BTW, beautiful truck. Your twin is hattrick's D-35 listed as a D-30 (long story).

Engine size appears to be 241 cu in OHV six cylinder.
University of Wisconsin has the IHC archives.
You can use your ID plate to see when it was produced and how many were made.

I have two D-30 engine/trans to look at here. I'm going to see if back of trans looks like yours.
Again, I'm going to get my butt kicked but I think my trans is IHC h-41? 4 speed no synchros.

Thanks Smog for all the info. I do agree that the gear it self may very well not be a problem. When I had the top end of the transmission apart I made sure to throughly clean everything as well as I could. Im still somewhat amazed that the top half of that gear was so pitted. Most of the pits were clustered together and were close to a 32nd " deep.Naturally the height of the gear left it not submerged in the oil bath. That along with the condensation being in the upper half of the trans must of made the perfect enviorment for the corrosion.

I found that this series of D trucks isnt very common here in Ill. either. Being that parts are somewhat scarce and the trans seems quiet I may just leave it for now until I can find a better donor gear.

This truck actually used to be a pumper fire truck so chances are most of the miles on the speedometer are pumping hours. Mechanically the the truck is very low wear. I consider myself VERY fortunate!

Actually shifting the non sync trans isnt to bad with some practice. But I will be honest adapting a T-98 would be great. The drive shaft to the carrier bearing will have to be made regardless of my choice though. The pump itself has not been removed yet and the original shaft has already been severly shortened. Im actually a certified welder and have a good ammount of experience in machining with the benifit of owning a mill, lathe and welding machines. However, the time/vs. the benifit will have to be weighed out. In so many words, "If it ain't broke don't fix it" mentallity comes to mind.

I am somewhat curious about the interchangability between series of D trucks. You just really dont see them to often to make the physical comparisons. It will be interesting to see if your trans looks the same as mine. Either way Thank YOU for all your effort!!!!!!!!!!!!!!!!

The engine according to the truck ID tag is a FAC 259, the wetliner predecesor to the BLD dryliner series. Unless the gears are severaly pitted, would run as is. Light pitting will wear and not hurt much. If later you want to change or a good used trans come along, then pull it.

You are welcome hotrodbrent.
I'd like to see your low mileage D-35 someday. Most of the stuff I drag home is beat.
I have B, C and D series two piece driveshafts. Not only do I save them from my projects I save them from the wrecking yards when I see them.
How do I know they're IHC in a sea of dshafts?
Red shafts with mechanics type u joints. They stick out.