I have a '78 f100 2wd with a dana 44 rear axle. The ratio is an anemic 2.72:1 I would like to swap it with a 9 inch with at least a 3:50:1 ratio from a newer truck. Has anyone else attempted this swap? Wondering if I will need a different driveshaft?

 

I thought all the 1/2 tons from that era came w/ 9" rears? I would assume this would be an easy swap. Driveshaft length? Probably won't change, but I can't say for sure.

 

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I've never seen a 44 rear on a ford WOW okay so every other F100-f150 came with a 9 inch 4wd f150 came with 3:50 as the standard gear ratio optians were 4:10 or 3:00 so the odds are if you find a F150 4wd in a bone yard with a 9 inch it'll be 3:50 and should bolt right in

 

I almost didn't believe it when I saw it, but I saw a Dana 44 rear in a 78/79 F1502WD in my local boneyard last summer. I think part of it was a light duty/ran out of the 9" rears at the factory type of deal.

 

I seems that some of the '77s and '78s had the oddball dana 44. This would be fine with me if the final ratio wasn't 2.72:1. This sux because I recently swaped in a fuel injected mustang engine with an aod. The overdrive gear is almost useless. What I really want is a 9inch with some sort of positraction. Maybe a 4x4 axle would be the best choice.

 

NPhunt, I'm not sure about the width but what about an 8.8 rear. There seem to be a lot around with the 3.55 limited slips. May need to make sure it isn't too wide and move the perches?

 

Unless it was installed bvy someone else & they changed the ring gear:
No Dana's on a F100 or 2x4 or in a 2.72 ratio
The lowest ratio was a 2.79 in a 9"

Please take a photo to make a liar out of me


Have a look here for the list of avialable axles in 1978 F & E-series trucks & Vans.

CLICK ME FOR Axle Codes

 

axle code is "02" which is not in that list. I am positive this is the factory axle; maybe sometime I will put pictures in my profile.



I wouldn't mind using an 8.8 I hammered the one in my mustang for years. Those are in '84 and up trucks right?

 

I have two 2wd F100's with Dana 44 rear axle, a 77 and 78. Door code on the 77 is 46j. Another reference to dana axle with 46j code.

 

I have a book that shows:
02 code w/3.00:1 ratio for 73-77 Vans (E-series)
02 code w/4.00:1 ratio for 61-68 Vans
02 code w/3.00:1 ratio for 81/82 Vans

 

I searched a few junkyards and found an 8.8 with limited slip and 3.73 gears in an 88 f150
I measured everything including the spring mounts, shock mounts, bolt pattern, and axle width and everything is exactly the same so I bought it for $100. I'll probably bolt it in tommorow and try it out.

 

Sweet, I have a 95 with the 5.0 Aod. Came with lame 3.08 open. I had the 3.73 limited slips put in and it made a world of difference. Sounds like you got a deal!!!

 

The 2.72 was a real honest ratio in a Dana 44 for the low GVWR trucks. It was axle code 46 to go with the standard front axle code of "8". Door tag will read "468".


It was the original rear in my (F10GEY40771) 1977 F-100 I bought new. I special ordered it in January of 1977 and the first truck got lost on a railroad siding between Mahwah N.J. and Babylon N.Y.

Ford admitted losing the truck and quickly built me another that I received on April 17, 1977. The "quicky" truck got what was "laying around" including some "almost" 1978 stuff and the 2.72:1 rear.

The originally ordered truck was found three weeks later and arrived at the dealership where the salesman invited me to see it to prove it was not a lie that they lost it.

It had the 3.00:1 Ford 9" I had hoped to get and the 302 had less anti-polution stuff on it. It also had the argent color wheels rather than the white ones I got.

All in all, I think I made out very well with F10GEY40771. It has been the best vehicle I have ever owned by a long shot.

It is not the fastest off the line with the 3.03 3-speed but holds it's own.

I was told (in the early 1980's) the radar gun read 126 MPH when it was flat out on level ground :-).

That isn't to bad for a stock loaf of bread being muscled through the air with an absolutely stock 302-2V.

Besides that, it got a steady 17+ to 19 MPG in city driving and as high as 27.5 MPG highway with 25 being normal on a trip.

I towed a 28 foot long Airstream trailer for 2600 straight miles through the blue ridge mountains (the entire length of the Blue Ridge Parkway...both ways) and averaged over 14 MPG towing.

The rear would still be in the truck if I hadn't hit a broken off piece of a truck leaf spring that came up, bent the driveshaft, and cracked the pinion shaft......I was not happy :-(.

I transplanted in a Ford 9" form a 1974, 5500 GVWR, F-100 and got hold of a set of 2.75:1 gears from a Police Interceptor. This rear is a lot stronger with the oil bath outer bearings and the 9" but the 2:72's and the Dana 44 still did the job

 

We do have a 1978 with a Dana factory rear differential installed with a 2.72 built in Norfolk VA.