rear end
Laughing Gas
Joined: Nov 2000
Posts: 1,072
Likes: 3
From: tulsa
rear end
I have a 68 ford f-100. It has a 3 speed manual trans. I was wondering what gears it may have in the rear end. It does not have a tag on it. I do not really want to take the 3rd member out and count teeth.
New User
Joined: Jan 2008
Posts: 0
Likes: 24
rear end
This has been mentioned MANY times.
Jack the rear end of the truck up.
Make a chaulk mark on the tire near the trewad.
Now,make a corresponding mark on the floor,gravel
whatever you have.
Now while you're turning the Wheel/tire ONE Revolution
COUNT the number of times the driveshaft turns.
This is the gear ratio.
ie:
3 turns =3.00:1
3 1/2 turns = 3.50:1
2 3/4 turns = 2.75/2.79: 1
3 1/4 = 3.25:1
4 1/8 turns = 4.11:1
Okay?
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
Jack the rear end of the truck up.
Make a chaulk mark on the tire near the trewad.
Now,make a corresponding mark on the floor,gravel
whatever you have.
Now while you're turning the Wheel/tire ONE Revolution
COUNT the number of times the driveshaft turns.
This is the gear ratio.
ie:
3 turns =3.00:1
3 1/2 turns = 3.50:1
2 3/4 turns = 2.75/2.79: 1
3 1/4 = 3.25:1
4 1/8 turns = 4.11:1
Okay?
Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving My Memory For When I Develop Alzheimer's"
78 F-150 429CJ,Silver
w/Explorer Pkge.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
84 Volvo DL Wagon
Senior User
Joined: Apr 2000
Posts: 170
Likes: 0
rear end
The above procedure only gives half the true ratio on a plain ol' non-posi rear end. For a 3.00, two wheel spins give 3 drive shaft turns, 18 wheel spins give 27 shaft turns, etc. If you have positive traction and jack up both wheels the number of times the shaft turns per wheel rotation is the gear ratio.
You may want to note that if you don't have positive traction and jack up one rear wheel, the truck will roll if it's on an incline.
Dan Blackwell
You may want to note that if you don't have positive traction and jack up one rear wheel, the truck will roll if it's on an incline.
Dan Blackwell
Elder User
Joined: Jan 2002
Posts: 525
Likes: 2
From: Mansfield, Texas
rear end
I just had a post about my rearend. If your are just wanting to know without guessing. Try this tip I got off my post. Place a piece on the bottom of your tire (6 o'clock). Then tape a 2 foot piece of string to your drive shaft (3 o'clock looking at the rear end) with the string coming out of the top of the tape. As the shaft will turn clockwise. Drive the truck forward on revolution of the tire. Count how many revs of string have gone around the tire.
2.75 turns=2.71
3.5 turns=3.50
4 turns=4.11
2.75 turns=2.71
3.5 turns=3.50
4 turns=4.11
