I know that the 9"s from 61 to 72 are a direct boltup for a slick, but Im looking for some specific things. (I think Bill has reminded me like 12 times on that)

What type of trucks should I be on the lookout for a 9" with preferably a 31 spline count axle shafts, and a trak lock/posi. Im not too concerned about gear ratio as I plan on doing a full rebuild on the axle anyway. The trak lock is the major point, as if I can save $300 over buying a new one and putting it in. 31 spline axles would be nice, but Im not going drag racing so a 28 count would be OK as well.

Thanks gents

 

I went to a local mustang restoration shop. They had a couple good condition used ones laying around and were happy to get rid of them for pretty cheap.

I stuck with an open diff. figured it's lasted 47 years so what's a few more. Will probably build up one when everything is back together to slap in there. At present time the state of the existing one is sucking up all of my available funds.

 

I know that some of the '78 & '79 Broncos had limited slips in the 9" but I'm not sure if they used the trak-Loc or something else. NumberDummy can narrow that down and what vin numbers to look for.

 

This is perfect for Mr. Wilson. Come on Bill lay it out for the man.




John

 

The only pre 1973 F100's with 31 spline axle shafts are 1968/72 F100's, with the heavy duty 3,600 lb. capacity 9" w/a 9 3/8" ring gear and 4 pinion Traction Lok.

All 1957/67 F100 9's have 28 spline axle shafts, as do the 1968/72's 9's without the 9 3/8" ring gear.

Only 5 parts are the same 9 vs 9 3/8: Housing gasket, pinion seal, one pinion bearing and race, pilot bearing retainer.

EVERYTHING else is different! Some of these parts may be difficult to find, especially the axle shafts.

1959/67 F100's, some 1968 F100's when ordered with Limited Slip came with Dana 44's, some 1963/66 F100's came with Dana 60.2's, some 1966/68 F100's came with Dana 60.3's.

The 5 lug 5.50" bolt pattern Dana 60.2 & 60.3's are not Dana 60's, which were only installed in F250's.

After 1972, the 9's could have 28 splines, could have 31 splines as it depended on the applications.

1959 thru today: If the AXLE code begins with a letter = Limited Slip. If with a number, no Limited Slip.

John may chime in, say you cannot go by Warranty Plate AXLE codes, cuz after decades have passed by, the axle may not be original.

But the Warranty Plate AXLE codes are better than nothing, because many of the rear axle ID tags are missing by now.

Plus, it's a lot easier to open the door, look at a Warranty Plate, than it is to crawl on hands and knees under a truck in a filthy junkyard, possibly inhabited with snakes and/or black widow spiders, looking for a rear axle tag.