Hosed Up My Rear End

[FordNut]

Now what?

I replaced the yoke when I swapped the transmission and driveshaft, upgraded to a conventional yoke with 1350 series u-joints instead of the companion flange. It had a little leakage, the seal is different and I didn't know it. No noise or vibration at that time, though. I swapped the seal the other day and apparently over-tightened the nut attaching the yoke to the pinion gear. I drove it around the block and now the rear end has noise and a vibration whereas it used to be smooth as silk. Maybe it's not tight enough but it's more likely that it has been over-tightened.

So do I have to pull the whole thing apart and put a new crush sleeve on the pinion gear now?

[Got_1]

i'd double check it first to make sure its not too loose. its very difficult to overtighten once the crush collar has been set. i replace pinion seals all the time at work and i hit that nut with my impact gun until it stops turning. never a problem. i have however, left them too loose (in my earlier days) and i had a hell of a noise/vibration from the rear end, brought it back in, hit it with the gun, all was well!!

EDIT** i no thats not the book way ^^^ but it works so don't flame me.

[Stranger in the Black Sedan]

^^ oh lord thank god I do my own diffs now. That is just scary.

[Dr Caleb]

I don't know why, but I expected this to be an enema thread.

[FordNut]

It was too tight. Either too tight or too loose and it makes noise & vibrates. Fortunately it doesn't appear to have caused any permanent damage.

Totally unlike the old 9" rear ends, tighten the snot out of 'em. I suppose you could convert it from a crush sleeve to shims, but I'll leave it alone for now.

[Phrog_gunner]

^^ oh lord thank god I do my own diffs now. That is just scary.

They should invent a type of wrench that tells you how much torque you are applying so that you can tighten something just the right amount.


Fordnut....glad to see you have your problem solved and no damage was caused.

[FordNut]

The "correct" method for an 8.8" involves pulling the brake rotors and torque in the inch-pounds range.

[FordNut]

^^ oh lord thank god I do my own diffs now. That is just scary.

And I understand exactly what you're saying.

[Got_1]

^^ oh lord thank god I do my own diffs now. That is just scary.


you'd be suprised (or maybe not) how many short cuts are taken in shops. But trust me, old techs have been doing this method for forever now

[Stranger in the Black Sedan]

Oh I believe you, hence doing my own work whenever possible.

[FordNut]

you'd be suprised (or maybe not) how many short cuts are taken in shops. But trust me, old techs have been doing this method for forever now

Well, it's totally wrong. Even the guy who sold me the correct seal told me to be very careful not to over-tighten the nut. And if the rear end makes any noise at all on the test drive, don't drive it or there will be many more parts to replace. And great expense.

[Got_1]

i agree that initial setup is important but once the crush collar is collapsed, it is quite difficult to crush it even further. obviously with an impact gun you can keep hammering and hammering and you will overtighten it. all you need to do is take a punch and mark the location of the nut in relation to the pinion flange, then once you reinstall the nut you hit it with a gun until its lined back up. done and done. no damage done.

[FordNut]

Wow. Are you ASE certified?

[Got_1]

no i'm an apprentice but who do you think is teaching me. I know the correct way to set pinion depth and ring/pinion clearance but ford doesn't pay enough to do it the "book" way. That is why i was also taught the "real world" way.

[carfixer]

The correct way to replace the seal is to mark everything before you disassemble and retighten to the marks. If you overtighten the pinion flange nut, replace the crush collar.

[Phrog_gunner]

i agree that initial setup is important but once the crush collar is collapsed, it is quite difficult to crush it even further. obviously with an impact gun you can keep hammering and hammering and you will overtighten it. all you need to do is take a punch and mark the location of the nut in relation to the pinion flange, then once you reinstall the nut you hit it with a gun until its lined back up. done and done. no damage done.

So when you line things up, theres NO chance you can be one turn too tight or one turn too lose when you just line up two marks? I always told my Marines that torque wrenches are idiot proof. I guess I was wrong, you have to actually USE the torque wrench for it to be failsafe.

[carfixer]

You don't torque the nut to a value, you torque the nut till you get the correct rotational value of the pinion flange.

So when you line things up, theres NO chance you can be one turn too tight or one turn too lose when you just line up two marks? I always told my Marines that torque wrenches are idiot proof. I guess I was wrong, you have to actually USE the torque wrench for it to be failsafe.

[Phrog_gunner]

You don't torque the nut to a value, you torque the nut till you get the correct rotational value of the pinion flange.

I learn something new everyday......:beer: But if you put in a new crush washer, like you are supposed to, then doesn't that mean your marks will most likely not line up, if you are using the "line up the marks" method??

[FordNut]

If you overtighten the pinion flange nut, replace the crush collar.

That's what I was afraid I was gonna have to do. Fortunately I didn't overtighten it enough to do serious damage. I guess I could have just hit it with the air impact, that would do wonders! :rolleyes: