81 F100 Bolt Pattern

Reply Subscribe

Thread Tools

Search this Thread

Feb 13, 2005 | 07:29 PM

sinchicken

Thread Starter

New User

Joined: Feb 2005

Posts: 9

Likes: 0

From: Hillsville, VA

81 F100 Bolt Pattern

This has probably been asked many times before, but can someone tell me what the lug pattern is for an 81 F100. I read somewhere it was 5x139, but I would like to make sure. Thanks in advance.

Feb 14, 2005 | 06:42 AM

82F100SWB

Post Fiend

Joined: Jan 2000

Posts: 5,330

Likes: 17

From: Dryden, ON, Canada

If the truck has manual brakes, it's 5x5.5", if it has power brakes, it may be 5x4.5" instead.

Feb 14, 2005 | 11:20 AM

sinchicken

Thread Starter

New User

Joined: Feb 2005

Posts: 9

Likes: 0

From: Hillsville, VA

Thanks.

It has power brakes.

Forgive me for my ignorance, but how do you measure it?

Feb 14, 2005 | 02:53 PM

Boss50

Elder User

Joined: Feb 2003

Posts: 871

Likes: 0

From: Coleman, Wisconsin

My '81 has power brakes and has 5x5.5 bolt pattern.

Feb 14, 2005 | 03:15 PM

mtflat

Lead Driver

Joined: Oct 1999

Posts: 6,779

Likes: 558

From: Kalispell, MT

Measure from the center of one stud to an imaginary arc running between the opposite two bolts. The difference of an inch will be obvious.

Ford didn't go with a metric pattern until 1997/98