87 Ranger Rear Pinon Nut Size??

[bottledgt]

wow...theres just too much wrong info everywhere. i dont even know where to begin and i dont think youd even understand if i did. are you telling me you tightened the big nut to around 29 IN LBS???? AND you took off all the crimp so the nut has no holding power. WOW. you know there is a big difference in rotational torque spec and tightening torque spec right? and believing AUTOZONE of all places will surely lead to failure. you cant even use the in lb specs if you leave a ll the guts in the rear. and im about done,im tired of trying to make people comprehend,it aint workin

 

[bottledgt]

yeah take it all apart and save a whopping 2.50 on a crush sleeve, good choice

 

[aipaul]

Well can some expert clear things up for us? There's three compeletely different opinions here. I would never tighten the nut to over 200 ft-lbs as Evan says. 1 ft-lb = 12 in-lbs so that would be 2400 in-lbs .

bottledgt seems to be saying that you can't just change the pinion seal without taking the gears out of the diff and using a new crush sleeve. Am I right? I've read lots of post and articles that say you can with the in-lb torque wrench.

 

[aipaul]

you cant even use the in lb specs if you leave a ll the guts in the rear. and im about done,im tired of trying to make people comprehend,it aint workin

All I can say is my truck has been "workin" better than it ever has and the nut has nut backed off at all in 3 weeks. I'll keep checking it to be sure though for a little while more.

 

[bottledgt]

you dont torque the nut to 29 in lbs. thats the rotaional torque. this is not opinion, this is fact

 

[aipaul]

you dont torque the nut to 29 in lbs. thats the rotaional torque. this is not opinion, this is fact

Okay I see what you are saying. I'll get a new pinion nut and try again. I wouldn't want the nut to back out and the driveshaft come loose.

 

[bottledgt]

and you cant even use that figure with anything but the pinion in the housing,. technically you have to figure in a little extra for the seal being there

 

[Evan]

Well can some expert clear things up for us? There's three compeletely different opinions here. I would never tighten the nut to over 200 ft-lbs as Evan says. 1 ft-lb = 12 in-lbs so that would be 2400 in-lbs .

Based on your post here, you need to find someone who is knowledgeable on diffs and gear setup to help you out in person. Bearing preload and locknut torque are two separate measurements. You seem to be treating them as one. If you refuse to tighten your locknut to over 200 ft. lbs. as you said, it would probably be impossible for you to set up a new crush sleeve.

Setting up gears is a pretty complicated process that requires everything to be just right. It's very difficult to describe the process well on a forum. I think that's why this is so troublesome. If you are already familiar with the process, you could rely on a forum to answer one question, but it's just too hard for people to describe an entire process.

I know MAKG and bottledgt know what they're doing. I myself have a lot of experience and a good track record of working on diffs. I think many of the disagreements or seemingly conflicting posts on this thread are a result of a breakdown in communication.

Like I said, my advice at this point is to find someone who knows what they're doing to help you in person. It's just too difficult to clearly define what needs to be done in a few sentances of text.

 

[MAKG]

The rule of thumb on differentials is to be utterly anal. Screwups tend to destroy everything in the rear end.

The Ford chassis shop manual (1986 and 1991 are the ones I've checked) says to replace the crush sleeve whenever the pinion nut is removed. The shop manuals are very far from Gospel; there are occasional whopping mistakes in there. But it does represent the training given to factory technicians.

You're probably OK following Evan's advice. Though I really think the 200 ft-lb spec is enough to move the crush sleeve. I'm not comfortable giving advice that conflicts directly with factory training, so I won't.

 

[AllanD]

You misunderstood my post(s). 200 ft. lbs is the spec for the torque on the pinion locknut when you're tightening it down with an existing crush sleeve.

That's different than the bearing preload, which should be measured with in. lbs. as you said.

And I'll finally jump in and say "you read the spec wrong"

The MINIMUM tightening torque spec to crush a new spacer is >160ft/lb.... the actual torque requires is usually far higher.
and can be >300ft/lb

I'll tell you with a straight face that if you run the nut down to start crushing the sleeve and it crushes with less than 200ft/lb
of torque stop, take it out and buy one from a different supplier
because the one you have is too soft...

I own a 3/4" drive torque wrench that is no foolin' four FEET long and even with my 300lb body pushing that wrench I've pulled muscles tightening those nuts.
I made my own pinion flange holding tool because I thought the factory one was "worthless and weak"
my flange holding tool is a 3foot long piece of 3/8" thick flat bar with a C-clamp welded to the "off end" so it can be clamped to the leaf spring.

BTW, my "Biggus Wrenchus" can effortlessly snap off the threaded shank on FWD outer CV's

FYI, The spacer does NOT control preload, it controls resistance against rotating the nut but much more importantly it acts as an anti-rotation device for the slip fit inner race of the front bearing. (This is what FORD says it's there for)

So replacing it isn't "nice", but really necissary.

Ever have an axle where you could not get the pinion out of the front bearing after you removed the nut and flange?
Invariably someone had it apart before you and re-used the crush sleeve and that allowed the inner race to wear a groove on the shank of the pinion.

IRS explorers do this because trheir aluminumdiff housing is "compressible" under hard acceleration loads...
it's why their diffs "self destruct"

If you want to be able to freely assemble and disassemble withoout replaceing the crush spacer you need a solid non-crushable spacer and a special shim kit, Moser (and others) sell these kits.

I regard MAKG's advise of "be anal" the simplest form advise on rear axle setup I can think of.

Do remember that the most highly stressed parts in your entire truck are ALL inside the diff housing, yes those parts are designed witha fair ammount of "overkill" but still the safety margin isn't as great as we sometimes would wish.

shortcuts can create annoying problems later.

AD

 

[bottledgt]

damn at least somebody agrees with me finally

 

[High Desert Ranger]

And I'll finally jump in and say "you read the spec wrong"

The MINIMUM tightening torque spec to crush a new spacer is >160ft/lb.... the actual torque requires is usually far higher.
and can be >300ft/lb

I'll tell you with a straight face that if you run the nut down to start crushing the sleeve and it crushes with less than 200ft/lb
of torque stop, take it out and buy one from a different supplier
because the one you have is too soft...

I own a 3/4" drive torque wrench that is no foolin' four FEET long and even with my 300lb body pushing that wrench I've pulled muscles tightening those nuts.
I made my own pinion flange holding tool because I thought the factory one was "worthless and weak"
my flange holding tool is a 3foot long piece of 3/8" thick flat bar with a C-clamp welded to the "off end" so it can be clamped to the leaf spring.

BTW, my "Biggus Wrenchus" can effortlessly snap off the threaded shank on FWD outer CV's

FYI, The spacer does NOT control preload, it controls resistance against rotating the nut but much more importantly it acts as an anti-rotation device for the slip fit inner race of the front bearing. (This is what FORD says it's there for)

So replacing it isn't "nice", but really necissary.

Ever have an axle where you could not get the pinion out of the front bearing after you removed the nut and flange?
Invariably someone had it apart before you and re-used the crush sleeve and that allowed the inner race to wear a groove on the shank of the pinion.

IRS explorers do this because trheir aluminumdiff housing is "compressible" under hard acceleration loads...
it's why their diffs "self destruct"

If you want to be able to freely assemble and disassemble withoout replaceing the crush spacer you need a solid non-crushable spacer and a special shim kit, Moser (and others) sell these kits.

I regard MAKG's advise of "be anal" the simplest form advise on rear axle setup I can think of.

Do remember that the most highly stressed parts in your entire truck are ALL inside the diff housing, yes those parts are designed witha fair ammount of "overkill" but still the safety margin isn't as great as we sometimes would wish.

shortcuts can create annoying problems later.

AD

So in essence, there is no simple way to replace the pinon seal without a bit of work?

The old rear end in my truck needed the pinon seal replaced and without any thought about it, gunned it off with the half-inch impact. Replaced the seal and gunned the pinon flange back on. Never torqued anything. Some time later probably 6 months the rear end started making noise and come to find out knocked 4 teeth in a row off the ring gear. (And no there was no noticeable slop in the pinon)

 

[Sasquatch_Ryda]

And this is exactly why I run a solid spacer instead of a crush sleeve, its a 5 minute job to change a pinion seal that way...

 

[AllanD]

The Pinion nut is 1-1/16" or a 27mm.

I personally prefer something in a 3/4drive.

Preferably atleast 24" long.

My 3/4-drive torque wrench is 42" long


Comments interleaved in RED

The torque of the locknut does NOT determine the bearing preload. The preload is determined by the amount the crush sleeve is crushed. This is set by HOW FAR you crank the locknut down, the torque applied to do this is near-constant and around 350-400 ft. lbs. but is irrelevant.

While torque is not specifically not relevant, exact position of the nut is. "torque" is an unknown variable due to differences in stiffness of the crush sleeve.

the Crush sleeve is not for determining "preload" but according to Ford
is primarily an anti-rotation device for the inner race of the "slip fit" front pinion bearing.



Once you have the crush sleeve and preload set up, you are free to remove the locknut and reinstall is as many times as you want. The torque spec for reinstalling a nut (with an existing crush sleeve) is about 200 ft. lbs., according to my Chilton manual. I have removed and reinstalled locknuts and internals on countless diffs, using the existing sleeve without any problems.

Yes, and I've replaced countless pinions on diffs where the lack of front inner race tensionallowed the inner race to rotate on the pinion shank creating a raised lip that made it all but impossible to remove the pinion fromn the bearing without destroying it (by buggering the threaded stub while driving it out of the "slip fit" bearing)

Obviously if you re-torqued the bolt to 400 ft. lbs. you'd risk crushing the sleeve more and increasing your preload. Or if you torque it under the Chilton spec of 200 ft. lbs. it may loosen and the preload will be under spec.

Actually 400ft/lb is greatly in excess of what would be required to snap the threaded stud off the pinion

There is no torque spec on the locknut when setting up a NEW crush sleeve.
Actually there Is a factory torque spec, but it is only a MINIMUM spec and is related almost entirely towards identifying a crush sleeve that is TOO SOFT to do it's job.

its 1 1/16th and no you cant keep taking the pinion nut off and on. i dont care what chiltons says. you can get lucky yes, but i wish you did rearends around here so i could make money fixing them all

AMEN!

If you're using the existing crush sleeve, your goal is not to crush the sleeve at all, as it's already crushed to spec for the gears. If you torque the nut to 200 ft. lbs. the sleeve should remain as-is.

If you are setting up the preload for the first time with a new sleeve, you're right; there is no way to put a number on the amount of torque. You keep cranking the nut down until the preload is in spec.

Frankly? Reusing a crush sleeve under any circumstances is a receipe for failure.

The non-crushable spacers make both the tension of the nut and position of the nut more or less irrelevant unless you over-gorilla
the nut and stretch the pinion shank (There is no conservation of stupidity in the universe)

But when using a solid spacer getting the nut tight enough so it won't back off is the only relevant criteria and that takes 250-ish

Also remember that when setting up a rear there is a great temptationto "over anal" things, like many "kits" include
races for the pinion bearings. herein lies another issue.

Even specifically trained, experienced professional mechanics
using the exactly specified specialty tools to install
the pinion bearing races can almost never get them as completely seated as simply driving the vehicle around the block once will.

So no matter how carefully you may think you have them seated
they will usually settle in further, resulting in the clearances (and preload) relaxing (I.E. get loose)

According to Ford only replace the bearing races if they absolutely NEED to be replaced.

On my own truck I replace my pinion races, however I plan on taking it apart again after about a month to reset the pinion preload, because I expect it to open up.

Personally I like replacing things at my own convenience rather than the convenience of my truck.

as for pinion bearing preload?
Even with new bearings and the seal it should be ~20in/lb
and that is the torque required to make it KEEP rotating, not the torque to make it START rotating (which is typically 50-100% higher).

On another note, with preload at the low end of the tolerance range... 8in/lb, a NEW pinion seal on an ungrooved pinion flange seal journal typically takes 3-4in/lb of torque just to overcome the drag from the seal.

I got kinda burned out doing axles because I got tired of dealing with people who kept telling me that how they did it was "good enough" and their while I was repairing the carnage from their self-proclaimed "expertise" and all the implied contradictions that entails.

Or people who'd come to watch an axle being assembled
and get all indignant that I wouldn't replace the bearing races
and that the issue wasn't open for discussion.
(not if they wanted me to stand behind the work)

Frankly if I needed to replace the races I'd often
set-aside that housing and use one that didn't need races.

Races that have been run are ALWAYS completely settled.

I've been thinking of making a "dummy pinion" (machined to be slip fit to both races) and a pair of new rollers (assembled without a seal) to use them to seat races after smearing the races (liberally) with Loctite RC680 and thus gluing the races into place so once the retaining compound is set the only way they will move is if the entire case fractures.

BTW, if the REAR race settles after assembly it also disturbs pinion depth.... another can of worms each of which has big
ugly biting teeth.



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[bottledgt]

while i agree with most of that allen...heres a tip on races. after installing them, and after reaching preload on crush sleeve, take a large brass punch and hammer. smack rear and front of pinion 3-4 times each. many times you will notice a preload loosening. tighten nut to spec again and repeat until preload stays. i have NEVER had a failure in over 10 years