1951 L150... What diff do i have?

Hello... I have a 1951 international L150 and would like some help to identify the rear differential. This L150 has the 6x7.25 bolt pattern, that will be my next issue. I have read the stampings on the diff and here's what i see...

8 7 50 __________ Date code I assume
82769R1 ________ ???
R ______________ Looks to be stamped into housing
837 ____________ Stamped... Gear ratio ???

I also see what looks like an IH logo. I have read that there were IH branded diffs or something like that, but finding info has been difficult for me. Any info would be appreciated... If i am correct about the 837 stampings being the gearing, then that would explain my top speed being soooo slow. I would like to start by keeping the truck stock, so maybe regearing would let me drive at a slow but reasonable speed.

Nice truck! And with all the grille chrome, too!

According to this page: http://content.wisconsinhistory.org/cdm ... 891/rec/10
the options were 4.88 to 1, 5.571 to 1, or 6.166 to 1. You could jack up the back end and turn the driveline by hand counting how many turns it takes to turn the tires once.

Or you can remove the strap holding the rear U joint on the pinion and look on the head of the pinion for the tooth count, expressed like 9-37, divide the big number by the small for the ratio.

Jared... That link is really good... A lot of info about the L150.

Cornbinder89... I'll check that number tomorrow. One never knows if the gears are origional.

I do have an original factory parts manual and it lists up to 6.17 gears in it but the numbers stamped in the picture show 837. Someone may have ordered it to really haul stuff around their farm.

I still don't know what diff it is... It's hard to google information when I don't know what to call it. Does anyone know who made it, or what type of diff it is?

Cornbinder89... I'll check that number tomorrow. One never knows if the gears are origional.

?

When I want to know what the ratio is I always go for the tooth count. It never lies even if the gears have been changed. whats stamped on the head of the pinion IS WHAT is inside.
IHC made their own rears.

837 is definitely not the ratio,what's in the MT-65 is what was available period. The pn 82769R? is for the carrier only I believe(?) does it match any in your parts book? It is an IH axle for sure,which will make finding anyhing other than bearings and seals improbable.

You could try a web search anyway,ya never know...
A hint on using IH pn's in web searches...even though they are printed with spaces leave them out in searches and you're more likely to get hits.

If you're considering finding a complete different axle and wish to keep it IH the later 1500's,1510 or 500 series are the equal to yours.Just keep in mind parts for those IH rears don't grow on trees either.

Scottso... Do you know what years of the 1500, 1510, and 500 series trucks had those diffs? Were they the same 6x7.25 bolt pattern, or would i be using just the inner assembly?

I figure the easiest way to regear would be to take the entire assembly out of a donor axle. if i have to get it shipped, it would be smaller and slightly less weight. I still don't know what the diffs name is... Like the dana44' chry8.25 etc.


Cornbinder89... I looked at the end of the pinion gear today, it had the IH symbol and what looked like... 82773-R2 FW 6-37... The first five numbers looks like an IH part number but its not in the back of the parts manual i have.

6.166666666 ratio or 6.17... easy enough and a very common ratio from what I've seen.

Thanks... At least i know what i have for now. Do you know what would be on the end of the 4.88 pinion shaft? If i go hunting for old diffs it would be the easiest way to tell whats inside.

Your last numbers (6-37) is the tooth count. SO look for the tooth count on what ever your looking at and divide the bigger by the smaller.