Tolerable Tolerances

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TillieTheTouring
Posts: 13
Joined: Mon Apr 15, 2024 10:41 am
First Name: William
Last Name: Naquin
* REQUIRED* Type and Year of Model Ts owned: 1920 Touring
Location: Gloucester Virginia

Tolerable Tolerances

Post by TillieTheTouring » Wed Sep 17, 2025 8:35 am

Deep into the rear axle now. Id like to ask for the acceptable range of tolerances as measured on a caliper guage for: 1) rear axle beyond the spindle; 2) axle sleeve; 3) the bearing itself. Thanks.

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Mark Gregush
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* REQUIRED* Type and Year of Model Ts owned: 1925 cutdown PU, 1948 F2 Ford flat head 6 pickup 3 speed
Location: Portland Or
Board Member Since: 1999

Re: Tolerable Tolerances

Post by Mark Gregush » Wed Sep 17, 2025 9:36 am

For the rollers you want ones that do not have loose cages and have a roller diameter of .498 to .500 at both ends. Some of the replacement sleeves are a little thicker so you could get by with a bit smaller on the roller diameter, but only maybe .001-.002 smaller.
The sleeves should be smooth without any worn areas at the ends. Inner ones are normally less worn, the outer ones can show wear at the top outer ends. The sleeves come in left and right to fit the ends of each housing.
Not sure right now about the bearing surface area diameter for the axels but suggest doing an online search by typing "MTFCA: axle diameter" in your search box.
I know the voices aren't real but damn they have some good ideas! :shock:

1925 Cut down pickup
1948 Ford F2 pickup


Topic author
TillieTheTouring
Posts: 13
Joined: Mon Apr 15, 2024 10:41 am
First Name: William
Last Name: Naquin
* REQUIRED* Type and Year of Model Ts owned: 1920 Touring
Location: Gloucester Virginia

Re: Tolerable Tolerances

Post by TillieTheTouring » Thu Sep 18, 2025 9:47 am

Thanks very much!


Scott_Conger
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Re: Tolerable Tolerances

Post by Scott_Conger » Thu Sep 18, 2025 10:25 am

This is not a criticism, but an observation: since you are asking those questions, this is your first rebuild, and as such, you are almost certainly not aware of other questions regarding wear/tolerances which are critical to a safe and reliable rebuild. If this is the case, then you need to order a rear axle rebuild book from any of the usual suppliers. Answers to every question you have asked and SHOULD be asking are covered, and tolerances and solutions are provided. It is an indispensable and economical resource.
Scott Conger

Tyranny under the guise of law is still Tyranny

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