I am trying to determine the front axle in my '78 F250. GVW is 7300, axle type is B42, # on the front web of the housing is 620093R. Any help would be greatly appreciated, it looks like it is a high pinion and the webs supporting the pinion side are huge.
I believe the '78 250 was a Dana 44HD. 8 lug, 31 spline, bigger U-joint dana 44. This is one of the toughest front ends out there. Same U joints and axle size as the Ford Dana 60 (outer axle spline), just smaller ring and pinion
good answer XRAY!
there has been lots of people argue with me on this one....telling me that the D60 has much larger axles than the D44 front,
it takes the same axleshafts and ujoints in both on the F250 4x4!
as far as strength the only diffrence is the ring and pinion size and housing size is smaller on the 44. the brakes and hubs spindles should interchange.
the steering arm on either (d44 or d60) has 4 bolts holding the steering arm on.
unless your going to run monster boggers or abuse the truck the 44hd should do fine in good condition.
I donno maybe I am missing something here, I realize the 60 is bigger but for the expence what do you actually gain? please enlighten me because I hear alot of people switching to 60's just curious...
60's can be had with 35 spline shafts all the way to the hubs. Also the hubs are much stronger. But this can be canceled out now that we have warn and some of the other manufacturers making 4130 shafts for front axles.
The biggest thing that I can think of is the machismo factor. That and the insurance factor. For the Machismo guys it's like bragging about having polished heads. Will they ever see 7500 rpm and use all that flow? Probably not, but it's always nice to know that you could if you really wanted to. Same with the dana 60 fad. You might not ever take your truck on a 5+ rated trail or be hopping up and down in one spot with the throttle on the floor and super swampers churning like mad, but you could if you wanted too.
As for the insurance thing. I've snapped a regular 44 u-joint in the middle of nowhere late at night. I have no idea why it broke, I wasn't pounding on it, and it was brand new so it wasn't from past abuse. But I've never seen a stock truck like mine was at the time break a 60 shaft or u-joint. Did I mention that when the u-joint went it took the spider gears and the ring and pinion with it? After I got the warranty bill I was thinking that if I had to pay that much out it would be cheaper to buy a new one from a junkyard.
Now that I wrote a book after intending to only write two sentences... Did I completely miss the question or does my reasoning make any sense.
The 60 is way stronger than the 44. A thing to remember...the inner and outer axleshafts on these axles are two different diameters. Dana 44 has 1.300 inner, but the outer shaft is only slightly larger than 1.125. Dana 60 in that year truck has 1.500 inner and a 1.300 outer shaft. As someone else replied, this 1.300 outer shaft can be replaced with a 1.500 Dana 70 shaft (with matching hub). Not to mention much larger uj.s and thicker and larger R&P. The only difference between the D44 and HD44 are the wheel bearings, lug count and brakes.
mammoth bronc is right about the differance between the hd44 and 60. the hd 44 is stout, but not as stout as the 60. speaking from experiance my uncle had a hd44 and he kept breaking ght e outer shafts on it. swaped to a 60 and no prblems after 2 years. ford only put the hd44 in the hi-boy(last year made was 76) from what i understand. in the hi-boy models they had a dana 44 8 lug and also an hd44 8 lug. i think the dana 60's where very rare until the 77 models came out.
There is another problem with the D44 size that is not mentioned here, and that is that the axle size is not consistant for the entire axle length. Old Broncos and 1/2 tons both had the tappered axles. The D44HD, and Ch*by 1/2 tons had a solid shaft with the larger U-joints. These are the same U-joint (297 I believe) that Ford used on their 30 spline outter axle stubs for their D60. Only the Ch*by D60s went with the 35 spline set up, inner and outer and this was not until the late 70s. Agreed that the ring, pinion, and inner bearings are stronger on the Ford D60, but as the saying goes, a chain is only as strong as its weakest link, being the shared U-joint. I am not trying to provoc a theory that the D44HD is as strong as the D60, just that they share a common link that is typically the breaking point. I have sheared off and twisted the ends off of 31 spline 9" and not had a problem with my worked D44 with the axle swaps. The real problem with the D44 and D60 that cause so much carnage is those darn cup clips. To much torque, the clip flies off and the cup desides to come out shearing yokes..... They have those new U-joints that actually have a stud through the cup with a small retainer nut on top,,,,, for the whopping price of $180 a piece. OUCH, but a great Idea. Just my 2 cents
Don't see why you couldn't do the same thing with a good drill press and some tap's and dies. It would take some tinkering to get the joint greaseable, but I don't see it being something that the average guy couldn't do given time and some good tools.