Rear Axle Length

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72ScampTramp

72ScampTramp

Scamp Tramp
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Ok, I have a Dana 60 housing sitting thats been cut down to what I assume is the proper length. I sent the off a set of Moser standard 8 3/4 axles off to Moser to get cut and resplined. They keep telling me my numbers dont add up dispite me measuring several times and getting the same numbers. In the photo the red line represents the Pinion Center not the center of the of the rear cover.

Me and a few others came up with axle width of
OK I marked a line approximately center pinion and measured diagonal to the center of the axle flanges (center of axle flanges to keep the measurements as close to the same spots. I came up with 26 3/8 on the driver and 24 1/8. Which gives me a difference of 2 1/4 inch.



Does the axle measurements still stand?

Driver side 25.03
Pass side 23.59


Im looking to achieve a total of 50 5/8ths thats over all with brakes and such.
 

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contact this guy on facebook
https://www.facebook.com/JantzEngineering

he's like a dana head for a long time... when i had a jeep wrangler people on those forums recommended him for dana axle cuts and stuff

even if you can just talk to him on the phone i bet he will walk you through measurements and such or give you some advice

his phone number is listed on the facebook page under info
 
Ive been in talks with Dr. Diff (Cass). I'm just confused about why the numbers dont jive. I've measured and measured this several times and dont get anything different.
 
Why are you obsessing over this?

Cass gave you a number, I gave you numbers, I know some others have.

With the axle housing flange to flange length 45.25, and using a drum set up, it's going to be 50.55" wide. That's pretty dang close to 50.625... You're roughly 1/16" of from the desired width or, a 1/32ish spacer on each side... That's fricken THIN!

Get the axles at what Cass recommended or what I gave you, either should work fine. 24.96 and 23.58

BTW, you are forgetting the center pin spacing we spoke about the other night. ~1.75". The difference in axle lengths should be equal to the difference in tube lengths or right at 1.375".
 
No not obsessing. I have moser telling me im wrong. The numbers are wrong or something is wrong. I even mentioned that I had run this by several people and come up that im right. The guy told me that they or the numbers are wrong.
 
Stuff the dang tape into the housing and run it up against the center pin and get those numbers.
 
You know he never told me a number.

He said that when I measure from center pinion to axle edge the difference between the 2 sides you divide that by 2 and thats your offset.
 
Add 2.525 to both those numbers and you get the MAX length the axles can be.

25.3375
23.775

The other is to grab the inside edge of the side gear to get where engagement ends.

I can't get to any of the D60 Sure grips I have to measure.

My spreadsheet has a tube length, outside the housing to flange of: 14.5625 and 13.1875. The pass side number jives with yours, the drivers side doesn't BUT the overall is correct. so I'll assume the drivers tube side is right.
 
Nope sounds like you got the gap between side gear and carrier.
 
Still not it is my guess.

turn the tape so it's sitting vertical (won't grab) and stick it in there, once bottomed, turn it flat and slowly pull it out.
 
Ok putting the tape in till it hits the pin then laying the tape flat the tape pulls out about 1/8th inch when it catches.

22 3/4
21 1/8

picking the tape up and pulling out again it catches another lip at

21 7/8
20 1/4
 
I have been avoiding this thread but can't help but telling you what you have. This was a rear that was cut for a center shaft chassis car. I have seen some of these before. The rears originally have equal length axles and the pinion was offset to the left or drivers side. The hump in all mopars is off to the left as is all motors from the factory. When building a Chassis car The motors are usually centered. The rear you have is a B- body with 2 inches cut out of the Right. To correct this rear you need to cut 2 inches out of the left. Then you can put equal lengths back in and install it with the proper back space wheels. This is just what happened to alot of Danas. I have Factory A and B Danas They all have equal length Axles. A's are 53 B's are 55 flange to flange
 
Sorry Steve, trucks have equal length tune. I believe the OP's axle came from a truck.

Mopar cars do not have equal length tubes or axle lengths when running a Dana 60. Pull the axles out of a B body rear and stand them up next to each other, they aren't the same length. They will be 1 3/8 difference. I have at least one set of 68-70 B body D60 axles standing up in my garage if you'd like a picture.

Also have a factory DC A body rear and it's got different tube lengths/axles.

8.75's do have equal length axles. The center pumpkin takes up pinion offset.
 
I am sorry my mistake I should have said axle tubes. I will measure a B-body rear and see what the measurements are and post them
 
Oldmanmopar said:
I am sorry my mistake I should have said axle tubes. I will measure a B-body rear and see what the measurements are and post them
Click to expand...

The axle tubes will be 1 3/8" longer on drivers side as well. It's how you get the mopar drivetrain offset, 1 3/16" IIRC, in a D60 rear.

I bought a D60 that was in a Camaro a long time ago, hoping I could easily put it in a Duster cause it was the right width. Ended up having to cut it to make it work.

Here's a link from a mag article where they addressed it but didn't appear to explain the actual observed measurements.

http://www.moparmusclemagazine.com/...opp_0704_dana_60_rear_end_build/photo_05.html
 
So Rob I sent all that info over to Moser yesterday. The guy calls me today again telling me thats not what he needs and those measurements don't mean anything. So I went out again and measured again. See picture
He said straight up the axle tube is not center of the pinion. He said the center pin and center of the pinion are 2 differet things.
 

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OK here we go

24-21.375 = 2.625
2.625/2 = 1.3125
1.3125 is the amount of your pinion offset. Now to get an imaginary line in the middle of the axle assembly, which will make it line up with the carrier center pin, you add 1.3125 to the short side and subtract that same amount from the long side...the number should be equal.

24-1.3125 = 22.6875
21.375 + 1.3125 = 22.6875

22.6875 * 2 = 45.375

45.375 + 5.05 (brake standoff/backing plate thickness) = 50.425 without drum thickness

50.425 - 1.75 air gap = 48.675 total axle lengths

48.675/2 = 24.3375 per axle if centered

Now you have to add/subtract the pinion offset because one tube is longer than the other.

24.3375 - .65625 = 23.68125
23.68125 + 1.3125 = 24.99375 or 24.3375 = .65625 = 24.99375

So the axles need to be 23.68125 and 24.99375

I have a whole write up in a word doc I'll post up.
 
I think Cass did this you'd need to adjust it slightly for the 1.3125 offset you have versus the 1.375 in the example:
--------------------------------------------------------------------------------
Stock pinion offset, driver's side tube and axle is 1 3/8" longer than passenger's side.

Typical truck Dana 60 casting: 17.5" wide

Assembly width: 51"

½ housing offset measurement = .6875

Housing width: 51 - .125 - .125 - 2.4 - 2.4 - .125 - .125 = 45.7"

Tube lengths:
45.7 - 17.5 = 28.2

28.2 / 2 = 14.1

14.1 - .6875 = 13.41" total pass side length

13.41" - housing end width = Passenger's side tube length

13.41" + 1.375 = 14.79" total drivers side length

14.79" - housing end width = Driver's side tube length

Most Dana 60 spools and all 35 spline sure-grips use 30 degree pressure angle and 1.75" axle end gap.

Axle specs:
5 x 4 1/2" bolt pattern

2.830" center register

2.5" axle flange to wheel bearing journal (step)

6" axle flange diameter

MO-400 or ST-400 Green wheel bearing

Axle lengths (overall length, flange to end of spline):

51 - .125 - .125 - 1.75 = 49"

49 / 2 = 24.5"

24.5 - .6875 = 23.81" Passenger's side axle length

23.81 + 1.375 = 25.19" Driver's side axle length
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If you took .20 off each of those axle lengths, you're pretty dang close to yours.
 
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