Does anybody know where I can find what type of rear axle was used in a 1959 P350 delivery truck? or what the ratio is?
I'm thinking of purchasing one of the P350's with a Grumman aluminum body on it but I'm concerned about it not being able to do 55mph with its 223 inline and a low geared axle... Maybe an axle swap or some slightly higher gears would do the trick?

 

A 1959 P350 has a Timken B140 rear axle, same as the F350s of the era. Optional final drive ratios were 4.86/1, 5.14/1, and 5.83/1. There should be a data plate on the axle showing the ratio.

Also unique to the F350s and P350s was the 6 lug x 7.25" wheel bolt pattern. Swapping to a different axle isn't hard, but creates a mix match with the front axle. Remedies have been found there too, but not so simple. If it needs rear drums they are NLA.

If the truck has dual rear 16" wheels they are serviceable. If it has 17" single rear wheels it will be a challenge. The 17" single is called a widow maker, trade name for the rim is Firestone RH-5°. Most shops won't touch them. There are remedies, though. Stu

 

1959 P350 could also have a Spicer (Dana) 60. Axle ratios: 4.56-1 & 4.88-1

AXLE code stamped on the 2nd line-far right of the Rating Plate. Located on the right dash panel of the P Series Parcel Delivery.

Pic: Scroll down to 1959 applications.

 

Yup, Bill, I read right past that. Which means the truck could have the F250 hub and wheel spec 8 x 6.5" pattern. Which would be a much more favorable situation. Thx. Stu

 

Interesting... I will ask the seller how many lugs the rims have. I don't want to get involved with a Timken axles and split rims... not my idea of fun.

 

Ask him the tire size too. The 17" used on the F-250s, with 8 x 6.5" pattern, was also a widow maker RH-5°. There are replacement alternatives. Stu

 

He said it's got 6 lugs soooooo.... thats the bad news! The good news is that he says it has more modern 19.5 rims and tires on it.


I suppose swapping an axle isn't too crazy but then the fronts don't match like you guys pointed out. In for a penny, in for a pound I suppose as long as the purchase price reflects that!

 

The truck then is single rear wheel since no 6 x 7.25" pattern dually 19.5s were made. The wheels are Budd 70740s, a very desirable optional wheel set. An 8R19.5" tire is about 33.5" tall, which is about the same as a 7.50-17" tube type. Not friendly to highway speeds, but the best oem wheel set up you could hope for given the 6 lug pattern. If you do swap in a different axle, I know somebody looking for the 19.5s. Stu

 

Highway would freak me out in one of those... no way.


I was hoping to do 55mph for back roads but that might be a stretch with the gearing in the truck 2700-3500rpm with stock axles ( depending on gearing)on the 223 inline... yikes! Don't think it would last long.


Maybe a better solution would be a more modern rear axle and a 300 inline up front... Sort of convert the driveline to a 80's/90's F250 or something?

 

Or maybe keep the rear axle for now and do a Inline 300 with an AOD behind it out of an E350 and fab a new driveshaft?

 

No E350 came with AOD

 

That would be correct!


I did a bunch of learnin' tonight and it looks like a 300 with a ZF5 would be the way to go but would transfer the column shifter to a floor unit.


As far as auto's are concerned it looks like an e4od is it but then there is the computer aspect...


Not looking good for this project unless I can get it cheap...