Rearend Help

[matt_stan40]

i need help finding out what i will need to know about my rearend when i go to the junker to get a new one.

i have a 1968 F-100 four speed transmission on the floor, 4 wheel drive half ton

[FORDification]

You should have a 9" Ford rearend with a front-loading removeable third member. Any rearend from '65-'72 will fit, doesn't matter if it's 2WD or 4WD. However, unless you want to also be buying a new ring-and-pinion setup for the replacement you find, try to find one with the same gear ratio as what you have now, so the front and rear will match.

What's the problem with your existing rearend?

[matt_stan40]

i dont really know exactley what is wrong with my rearend but i do know that something is wrong. the driveshaft still rotates but the truck doesnt move so i know that it is something in the rearend. im just gonna go ahead and buy a junker rear end because i can get one for about 100 bucks. i would rather buy the whole rearend because i dont want to have to deal with any other parts in my current rearend going out once i would replace whatever is wrong with it now. the wire cables going to each brake drum in my rearend are going out and those type of brake cables arent made for fords this old anymore. the only thing i can do to solve this problem is either send my cables to Portland Oregon and get them repaired or try to find ones in better condition.

about the gear ratios, do you know anything about what mine may be?

[matt_stan40]

oh yah, when i look at rearends from '65-'72 does it matter if it is from a f100 or will any f series do?

[dcbullet]

oh yah, when i look at rearends from '65-'72 does it matter if it is from a f100 or will any f series do?

If you want to keep the same number of lugs in the front and back, you'll need to stick to F100, which have 5 lugs, versus F250, which have 87 lugs.

[spartman]

If you want to keep the same number of lugs in the front and back, you'll need to stick to F100, which have 5 lugs, versus F250, which have 87 lugs.[/quote]

Holly carp!!!!!

I wouldn't want a F250 if I had to change 87 lugs on a tire!!!

[dcbullet]

Oops, hit an extra key there!

8 lugs!

[1970F250]

[SmokeyBear]

Do you know your old gear ratio?If not there are several ways to tell...

1. probably the easyist, if it still has the tag it will be stamped on there.

2. most time conusming but most accurate. Take the pumpin off and count the ring gear and pinion gear.

3. You may not be able to do this one since you say the driveshaft turns but the truck does not. Jack up the rear end, make a mark on your driveline and wheel. Rotate your tire one complete turn and see how far your driveline rotates, it should give you a ballpark of the gear.

[stockr]

well if you dont want to hassel with it...it would be a good idea to get a junker...but if its a project truck i would keep it and just upgrade it...that way you dont have to worry about it for a long time...trust me i learn the hard way on my mustang...if your not in a hurry then its well worth it doing it right. thats just my advise...

[ToughOldFord]

If anything had 87 lugs per wheel it'd havta to an International.

[matt_stan40]

Junker says its gonna be 200-300 dollars for a new rear end. If anyone has a better deal and lives close to northern california or southern oregon leave a comment with info.

[jzjames]

junk yard differentials is one thing junkyards try to rob you on.
Keep looking, and let all their junk keep sitting there.

[rjewkes]

Also i had an old 77 (sorry Guys) Buick Electra that had the condition that reverse was the only gear that would move the rear end full weight on the tires. then if i removed the wieght (jacked up and supported the rear it would fly at 60-80mph.

I beleived the front edges of the pinoin where worn out. so maybe The rear end will move off of the ground.

[jeepermc]

My suggestion- this is a 4x4 right? If the rear is so bad you can't count teeth, check the front-end for a tag or count the front. You can check it without pulling the cover by jacking it up, turning the tire and counting the revolutions of the driveshaft....... It may be a few teeth off from the rear as most fords of our vintage are, but I don't know for sure. Most common for the 1/2 tons I believe is 3.50 gears......