Sorry..
Thread Starter
|
Post Fiend
Joined: Jun 2004
Posts: 8,147
Likes: 1
From: Joppa, Maryland
Sorry..
I know this has been covered a million times, but i just couldn't find exactly what i was looking for.
I originally had 245/75/16's on my truck, i now have 285/75/16's. This has effectively lowered my gear ratio, correct? I have a 3.55 rear. What should i put in as my new rear to correct my speedometer using my new diablo tuner?
Thanks guys,
Paul
I originally had 245/75/16's on my truck, i now have 285/75/16's. This has effectively lowered my gear ratio, correct? I have a 3.55 rear. What should i put in as my new rear to correct my speedometer using my new diablo tuner?
Thanks guys,
Paul
Posting Guru
Joined: Mar 2005
Posts: 2,068
Likes: 0
From: western montana
your height has changed as well- all 75,85 series height is based on width as well. So it is a good question...i don't have the answer but had to point out that your concern may be legitimate.
Laughing Gas
Joined: Jan 2004
Posts: 913
Likes: 2
From: Pensacola, FL
if i remember right, the 70/75/85 etc in the tire designation is a ratio of the width. so the old tire height was 75% of 245, while the new tire height is 75% of 285, the R is radial and the 16 is rim size.
this is assuming i remember correctly though, someone else will chime in here with the correct answer if i am wrong.
jamie
ps. the first number, the 245/285 whatever is measured in mm, so the height of the new tire would be 213.75 mm, the old tire size was 183.75 mm. like i said, this is assuming i am right( i am taking medicine for a major cold right now, so i might be thinking of something else.
this is assuming i remember correctly though, someone else will chime in here with the correct answer if i am wrong.
jamie
ps. the first number, the 245/285 whatever is measured in mm, so the height of the new tire would be 213.75 mm, the old tire size was 183.75 mm. like i said, this is assuming i am right( i am taking medicine for a major cold right now, so i might be thinking of something else.
Last edited by kermit; Jan 1, 2006 at 01:47 AM.
Lead Driver
Joined: Apr 2001
Posts: 6,335
Likes: 6
From: Midwest
Trending Topics
Laughing Gas
Joined: Jan 2004
Posts: 913
Likes: 2
From: Pensacola, FL
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Elder User
Joined: May 2003
Posts: 556
Likes: 0
From: Dixon, Il
If I remember correctly, the 245 or 285 is the width of the tire. The way I always figured it out was that 4 tires on their side should equal one standing up. Basically the 245 is 25% of the height on a 245/75/16r. This is if I remember things right this late at night.
Post Fiend
Joined: Mar 2003
Posts: 14,413
Likes: 3
From: Sarnia, Ontario, CANADA!
Originally Posted by Ford_Six
The sidewall height, 75 in this case, is the aspect ratio. That means that the sidewall is 75% of the width of the tread.
Thread moved to tires forum.
-Matt
Postmaster
Joined: Jun 2004
Posts: 2,646
Likes: 1
From: Milky Way Galaxy