I recently purchased this 39 truck,i believe it's a 3/4 ton judging from the 122" wheelbase and the heavier axle,but i'm just trying to find out a few things.

firstly it has a heavy duty axle on the rear,is there anywhere i could find out what gear ratio the axle is?

are there different gear sets available for this to make it more usable?

 

The stock ratio was 4.86/1 but there was an optional 4.11/1 available. But very rarely found. The Green Bible (Chassis Catalog) shows that the Timken used in 38/39 has different ring and pinion part numbers than 40-47 (or 48-52). If your goal is to keep its pure stock appearance (beautiful truck btw) a custom 4.11/1 set is available from Chuck Mantiglia of Chuck's Trucks in CT. I have these sets in both front and rear axles, and have read of others who happily have made the conversion. Chuck will know if his sets will fit the earlier Timken as well as the later ones. Below is a link to Chuck's site. Stu

Chucks Trucks LLC., Chuck's Trucks, Chucks Trucks

 

Thanks for the info stu and the link,i'd like to think if they went to the effort of restoring the truck they would have put decent gears in it.

would you know what sort of speed it would be good for with the stock gears?i'd like to use it alot and for long distances but don't want it screaming at 50mph.

i plan on keeping it pretty stock looking and would like to keep the original running gear,my only plans are to drop it a little and smaller tyres on the front.

 

Screaming at 50 is probably what you'll have. If you truly have a 3/4 ton with 16" wheels like used on the half tons you will have many tire options. If it is actually a one ton with 17" wheels and tires your tire options will be more limited. With either size wheel you could go with narrower tires which will also be slightly shorter in diameter. Otherwise you're looking at modern radials that might look wrong on the truck. Stu

 

Great looking truck!

 

This one is right in my wheelhouse! I daily drove a '38 tonner for ten years. According to 'Ford Trucks since 1905' by James Wagner, the 4.11 was standard gearing for the '38 tonner. Perhaps folks in hill country had trouble getting over the crest, because in '39 the gearing was lowered down a notch or two as standard. After a few flatheads over the years I settled on a 59ab with a 4" stroke Merc crank. Everything else stock. This was a tremendous help with the added torque. I kid you not, it was no problem whatsoever running on interstate 5 in the fast lane. I ran 7.50 17's measuring 34" diameter and with the 4.11 it did 65 easily. Do the math. Many modern one ton trucks run with 4.11s (ok, modern to me, like 70's, 80's and 90's), but they run tires that are usually 32" dia tops. They run down the interstates all day long. I was effectively geared higher than they were. I passed plenty of rigs with a tandem axle trailer in tow. Yes, I had cable brakes, but the trailer had well maintained electric brakes and that's what I used when towing. Just wanted you to know that what you desire is obtainable. It was actually a pleasure to drive and steered like it was on rails. Never a single thought about converting to power steering. Power brakes, well maybe. Gorgeous truck, you lucky dog, and a real tonner. Don't get much better than that!

 

Cool well it's got the 17" wheels with 7.50 tyres that are 33" tall, so shouldn't be too bad right?if it's got a 4.11 in that really would be great, I've got a french motor here with the 4" crank which might be worth getting rebuilt and in it?

 

No, you should ship that Frenchie to me! I checked out the info in Wagner's FTS05 last night. 4.11 for the '38, 4.86 for the '39 as standard. I have 2 of those rearends under trailers. Anybody know how I can tell the ratio? They both have the axle shafts removed. I do think I have one nos axle shaft laying around.

 

I've had them where the ring and pinion tooth count (34/7) was stamped into the case. The only original axles I've ever had were the 4.86/1 ratio, but I know a guy that has two original 4.11/1 equipped trucks. Stu

 

Mine has b63 or 863 stamped into mine one side and an r the other does*this mean anything?

 

Not that I can interpret, sorry. Another way to tell is by jacking up one rear corner with the opposite side firmly on the ground, then mark the drive shaft and raised wheel with chalk so you can count rotations of the shaft as you turn the wheel through its 360° rotation. A little over four should be the 4.11/1, a little less than five the 4.86/1. Stu

 

I guess you could do this and leave it in high gear and count the revolutions of the crank pulley. Unfortunately these trucks have an enclosed driveline. I would need another axle to do that method with the trailers. Oh wait I could put the axle shaft in the side set on the ground and whittle down a branch jambed into the splines and count that. I just can't believe how beautiful and stock your big pickup is. And that's from a lifelitme patina guy.

 

Oh yeah, '39 still had the torque tube on standard 2wd trucks. I slipped into M-H brain mode where I'm pretty sure they converted trucks to an open shaft. My bad. Stu

 

I'm remembering something wrong here. I just ran this past Chuck and he says MH didn't convert them to open shaft. So I've gotta figure out how I got my facts wrong. Sorry if I've confused things. Stu

 

That is pretty truck! I've always had a soft spot for the 38/39, maybe someday I'll get my hands on a 1 1/2 ton 4x4... with a plow... and a lincoln v12... I could go on for a while.

Sam