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| | | | Joined: Jan 2004 Posts: 288 Shop Shark | | Shop Shark Joined: Jan 2004 Posts: 288 | Monday I pulled the 245/75 r15's off the rear of my truck, mostly in part because they were getting cracked side walls, but really I wanted to go taller to lower the rpm's.
Wow, what a difference, so much so that I am not going to swap rear ends, I am gonna keep the stock rear with 3:90 gears, I am cuising comfortably at 60-65mph.
I am also running 225/75 r15's up front and I am sooooo happy that I don't have to change the rear end.
Now I can focus on the tie rod and sway bar issues.
Just wanted to share my experience with you all.
Thanks,
Chris
Chris 1955FirstSeries
| | | | | Joined: Oct 2002 Posts: 4,066 Bolter | | Bolter Joined: Oct 2002 Posts: 4,066 | Chris. is a 225/75 r 15/ taller then a 245/r75/15?? I thought the middle number was the height,,thanks..Fred
Redryder pixMy HotrodA veteran - whether active duty, retired, national guard, or reserve - is someone who, at one point in his or her life, wrote a blank check made payable to The 'United States of America', for an amount of "up to and including my life."I am fighting cancer and I am winning the fight | Pain is part of life; misery is an option. | | | | | Joined: Jan 2004 Posts: 288 Shop Shark | | Shop Shark Joined: Jan 2004 Posts: 288 | From what I was taught the middle number is the width, the lower the middle number the wider the tire, for example a 225/70 r 15 would be wider than a 225/75 r 15.
-Chris
Chris 1955FirstSeries
| | | | | Joined: Jan 2005 Posts: 1,682 Extreme Gabster | | Extreme Gabster Joined: Jan 2005 Posts: 1,682 | Thats the way I understood it.. the middle number is the width, the end number is the inside diameter, and the first number is the amount of rubber between the rim and the road.. the lower the number, the more rubber.
an idea is only stupid if you think about it rationally.
| | | | | Joined: Jul 2005 Posts: 88 Member | | Member Joined: Jul 2005 Posts: 88 | The middle number is the aspect ratio (% of the first number = tread width). | | | | | Joined: May 2005 Posts: 147 Shop Shark | | Shop Shark Joined: May 2005 Posts: 147 | | | | | | Joined: Mar 2005 Posts: 627 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 627 | Chris didn't say what tires are on the rear, but a 225/75 is shorter than the 225/75.
245 = 245 mm width
75 = height = 75% of the width = 183.75 mm
15 = inside diameter = 15 inches
225/75 height is less: 75% of 225 = 168.75 mm
Why mm and inches are mixed up in the same part number is baffling.
Mike Barnes
1950 GMC 1-ton pickup
| | | | | Joined: Mar 2005 Posts: 627 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 627 | Typo: 225/15 is shorter than 245/15!
Mike Barnes
1950 GMC 1-ton pickup
| | | | | Joined: Jan 2004 Posts: 288 Shop Shark | | Shop Shark Joined: Jan 2004 Posts: 288 | Sorry guys, brain fart on my part. I took the 245/75 r 15's off the rear and put on 265/75 r15's back on.
As [censored] Vitale would say "Awesome Baby".
Thanks,
Chris
Chris 1955FirstSeries
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