Hooo Hooo! it's running
Thread Starter
|
Logistics Pro
Joined: Jan 2001
Posts: 3,789
Likes: 26
From: Connecticut
Hooo Hooo! it's running
Did the oil change & changed the oil return pipe that was pinched,
Hit the button, and she fired right up, Wow what smoke!
Did the formula of rotating the rear tire 5 times and counting the pinion revs.
then divide by 10
Got 16 5/8 revs of the pinion/10 =1.6625.
Does this mean 6.62 gear ratio?
Thanks
Ron
Hit the button, and she fired right up, Wow what smoke!
Did the formula of rotating the rear tire 5 times and counting the pinion revs.
then divide by 10
Got 16 5/8 revs of the pinion/10 =1.6625.
Does this mean 6.62 gear ratio?
Thanks
Ron
Hotshot
Joined: Nov 2000
Posts: 11,591
Likes: 14
From: Pflugerville, tx
wrong calculation, that would be 16 5/8 divided by 5 or 16.625/5 = 3.325
sounds like a 3.27, which is 16.4/5
so the trick is to increase the wheel turns to eliminate the partial turn of the driveshaft
if you had turned the wheel 50 times you would have had 165, almost 166 turns, or 164 turns. 164/50 = 3.27
this is an established ratio, 3.08, 3.27, 3.55, 3.73, 4.11
Sam
sounds like a 3.27, which is 16.4/5
so the trick is to increase the wheel turns to eliminate the partial turn of the driveshaft
if you had turned the wheel 50 times you would have had 165, almost 166 turns, or 164 turns. 164/50 = 3.27
this is an established ratio, 3.08, 3.27, 3.55, 3.73, 4.11
Sam
Lead Driver
Joined: Aug 2002
Posts: 6,682
Likes: 12
From: Saskatoon SK Canada
What I do, is jack one tire up, mark it, then mark the driveshaft. Now one person turns the one rear tire 20 times, and the other person counts the driveshaft rotations. Then divide the resulting turns of the driveshaft by 10. If you count 35, then you have 3.50 gears..
Doing it this way will let you tell the difference between 3.00, and 3.10 gears.
This method works great. If your truck is an F-5, they did come with a 6.6 ratio.
Doing it this way will let you tell the difference between 3.00, and 3.10 gears.
This method works great. If your truck is an F-5, they did come with a 6.6 ratio.
Thread Starter
|
Logistics Pro
Joined: Jan 2001
Posts: 3,789
Likes: 26
From: Connecticut
It is an F-5.
so the 3's ratio doesn't seem correct.
Should I re-do the tire spin? I did mark the pinion and tire. It came out 5 tire rotations, 16 and about 5/8 pinion rotations
so the 3's ratio doesn't seem correct.
Should I re-do the tire spin? I did mark the pinion and tire. It came out 5 tire rotations, 16 and about 5/8 pinion rotations
Postmaster
Joined: Mar 2000
Posts: 3,730
Likes: 13
From: Waynesville, OH
Hold on a sec, guys, ya got me confused. 
1. Dueller mentioned one of the original F-5 rear end ratios is 6.66, and that matches the numbers in the parts book. Other options were apparently 5.83 and 5.14.
2. Ron, did you jack up only one side of the truck rear?
The formula is: Axle Ratio = (Pinion Revolutions) / (Wheel Revolutions X 2)
You can use any number of wheel revolutions you want - more revolutions will generally give you a more accurate axle ratio.
Examples:
You jack up only one side of the rear axle, turn the free wheel five complete revolutions, and get 66.6 complete pinion revolutions.
(66.6) / (5 x 2) = 6.66 Axle Ratio
You jack up only one side of the rear axle, turn the free wheel ten complete revolutions, and get .
(102.8) / (10 x 2) = 5.14 Axle Ratio
Have fun counting!
1. Dueller mentioned one of the original F-5 rear end ratios is 6.66, and that matches the numbers in the parts book. Other options were apparently 5.83 and 5.14.
2. Ron, did you jack up only one side of the truck rear?
The formula is: Axle Ratio = (Pinion Revolutions) / (Wheel Revolutions X 2)
You can use any number of wheel revolutions you want - more revolutions will generally give you a more accurate axle ratio.
Examples:
You jack up only one side of the rear axle, turn the free wheel five complete revolutions, and get 66.6 complete pinion revolutions.
(66.6) / (5 x 2) = 6.66 Axle Ratio
You jack up only one side of the rear axle, turn the free wheel ten complete revolutions, and get .
(102.8) / (10 x 2) = 5.14 Axle Ratio
Have fun counting!
Thread Starter
|
Logistics Pro
Joined: Jan 2001
Posts: 3,789
Likes: 26
From: Connecticut
Getting more confused.
This is an F-5.
Jacked up one side, Rotated the tire five times.
The pinion rotated 16 and 5/8 total times.
16.625/ (5x2)
16.625 / 10 = 1.6625.
What do you get from this?
This is an F-5.
Jacked up one side, Rotated the tire five times.
The pinion rotated 16 and 5/8 total times.
16.625/ (5x2)
16.625 / 10 = 1.6625.
What do you get from this?
Trending Topics
Hotshot
Joined: Nov 2000
Posts: 11,591
Likes: 14
From: Pflugerville, tx
Yes, Sorry, I was using the posi calc instead of the open diff calc.
On open diff it is axle rotations / (wheel rotations/2)
so 16.625/ (5/2) = 6.65
Sam
On open diff it is axle rotations / (wheel rotations/2)
so 16.625/ (5/2) = 6.65
Sam
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
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
Postmaster
Joined: Mar 2000
Posts: 3,730
Likes: 13
From: Waynesville, OH
Dang Ron, I screwed you up. Sorry man. 
I got a times 2 instead of a divide by 2. Thanks for the catch Sam.
As Same said, the formula is:
Axle Ratio = (Pinion Revolutions) / (Wheel Revolutions / 2)
I got a times 2 instead of a divide by 2. Thanks for the catch Sam. As Same said, the formula is:
Axle Ratio = (Pinion Revolutions) / (Wheel Revolutions / 2)
Thread
Thread Starter
Forum
Replies
Last Post
eman92082
1948 - 1956 F1, F100 & Larger F-Series Trucks
15
Feb 16, 2009 03:53 PM