Farm Equipment - Allis G rear tire size?

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Allis G rear tire size?

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Topic: Allis G rear tire size?

Posted By: Herb(GA)
Subject: Allis G rear tire size?
Date Posted: 30 Jan 2011 at 6:50am

Allis G original tire size was 6 x 30; todays tire size is 7.2 x 30. This original size was still listed in April 26, 1951 dealers "Agricultural Price List Book". What was the reason for this later size change? And when did this change occur?

Replies:

Posted By: DanD
Date Posted: 30 Jan 2011 at 7:19am

Here is a link to a website that will amswer most of your questions.

http://www.millertire.com/FAQs.asp - http://www.millertire.com/FAQs.asp

Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 10:23am

Tire sizes didn't change much, the numbers did. The old tire sizes were rim size for width. Later the number was changed too the maximum width of the tire. 7.2 is the same size tire as 6. The tire manufacturing association that set the standard arranged that most of the time they didn't use the same number for a tire width as had been used for a rim width usually keeping rim widths hole numbers and tire widths decimal numbers with a small fraction like the .2 in 7.2. I found a library collection of the tire standards at the ISU library and made note of the changes one time, but I don't remember the year the change was first an option or the year when they decided it was manditory. There probably were several years of overlap.

Later tires where changed again, especially road tires, to showing width and ratio of height to width. Most often used for radial tires with the width in millimeters instead of inches.

Gerald J.

Posted By: Dusty MI
Date Posted: 30 Jan 2011 at 7:42pm

When I acquired my G it had a 6x30 on one side and a 6.2x30 on the other. The 6x30 was shot so I went to a tire shop and had it replaced with a new 7.2x30. When I got home and stood the new 7.2 beside the 6.2 the 7.2 was 2" taller, so I had to go back to the tire shop and get another 7.2.

It's my understanding that the 6.2x30 is the same as 6x30 just new way of measuring.

But the 6.2 is no longer made and the next size is 7.2x30.

I heard a couple years ago that Miller Tire was going to have some 6.2x30 that summer, but never saw any.

Dusty

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917 H, '48 G, '65 D-10 series III "Allis Express"

Posted By: Gerald J.
Date Posted: 30 Jan 2011 at 8:28pm

6.2 is the new label for something smaller than 6, probably 5 x 30. 7.2 is the new label for the old 6x30.

Gerald J.