Rear End options

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Jan 17, 2024 | 03:14 PM

12Stratford

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5th Wheeling

Joined: Oct 2023

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Rear End options

My 66 F100 has a Dana 44 with 3.73.gears.. I'm looking to try out 2.73 gears for easier highway driving.I know this question has been asked a bunch but I can't seem to find a cear answer. Rather than swap out the Ring and pinion which seems like a lot of technical work, I'm wondering if there are other complete rear ends from donor cars that are suitable for the mF100. I dont mind changing spring perches or Shock brackets. It seems like the current rear has a pretty much center pumpkin. I saw a rear end out of a 96 F150 which was inexpensive, but the pumkin is affset to pass side. What units are easiest. Drum brales are fine but Bolt pattern of course is important for the easy part. I will keep the Dana 44 because I might not like the ratio that I change to and unbolting and reinstalling the original would be simple.

Jan 17, 2024 | 04:58 PM

john jamieson

Cargo Master

Joined: Jul 2015

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From: tucson

Any 2wd truck up to '72 should drop in. '73 to '79 axles are a little wider but a lot of people have swapped them in with no tire fitment problems.

Jan 17, 2024 | 06:40 PM

PROSTOCK

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Joined: Feb 2004

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From: Central Texas

Quote:

Originally Posted by john jamieson

Any 2wd truck up to '72 should drop in. '73 to '79 axles are a little wider but a lot of people have swapped them in with no tire fitment problems.

Not quite. While I agree with the width not being an issue, the spring perches and shock mounts will have to be moved in to match the '66. I put an '81 Dana 61 in my '65. Not hard to do and well worth the effort.

Jan 18, 2024 | 05:19 AM

Crop Duster

Logistics Pro

Joined: May 2015

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From: Tri Cities, TN

That Dana 44 is a desirable rear end and it most likely is a limited slip. As far as bolt in 9-inch rears 61-67 will bolt in with the same rear brakes, 68-72 is a bolt in with bigger rear brakes 73-79 will need modifications but has bigger brakes and most are 31 spline axles. If you swap you need the complete rear, drum to drum because there are differences that make mixing and matching parts impossible. For instance, when Ford went to bigger rear brakes in 1968, they did more than just put different backing plates and drums on. They shortened the housing and moved the bearing seats on the axles also.

Jan 18, 2024 | 03:35 PM

12Stratford

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5th Wheeling

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Thank you for the input. I realize my Dana44 with limited slip is a good one. Ill be keeping it. I'm a bit nutty and like the idea of being able to swap rear ends if my wife and I decide to buy a camper and tow it around. For now we want to do 65 on the highway and still hear eachother talking. So a 59 F100 rear end on Ebay would theoretically fit?

Jan 19, 2024 | 01:24 AM

66F250_4x4

More Turbo

Joined: Dec 2019

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From: Orange County

3.73 to 2.73 is a big jump, and the truck might feel overly sluggish compared to how it is now. (That happened to me,).
Making some assumptions about your set up. I'm guessing you could get half way there with taller tires if that worked for you. Could be an easier and cheaper mod than the axle swap, or at least a quick test if you found some cheap retreads or something.
And if quiet is the goal, investing in good sound proofing materials all around the cab and in the doors, and installing carpet from firewall to tank, and then also over the tank like the Rangers, did true wonders for my truck. I can talk to people now, kinda.

Jan 19, 2024 | 09:03 AM

12Stratford

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5th Wheeling

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Current tires are 28” on 17” rims

I found 9” from a 71 F100, 3.23 ratio. It’s not far from where I live. What are the odds that my driveshaft length will need to be changed if I try to drop the 9” where a Dana 44 sits now