Differential question - Pinion Bearings Replace or Not??

[tommudd]

Nothing confusing about it at all
Have NEVER had a need to use a 1/4 inch
Back when I owned XJs I did a bunch of 8.25s in them installing new lower gears /lockers etc
If you have the right torque wrench in 1/2 inch you do not need a small one .
I am quite familiar with the torque specs, no need to repeat them
I have had a flange holder that I made for over 20 years or so now at least and its not " store bought "
Guess I grew up in another generation and do not understand the new bunch of have to have this/that/ etc
I have a beam style ( 1/2 inch ) that is way older than most on here, I bought in 1970, and is checked every year or so along with my other two a Snap On and older Craftsman for accuracy

 

[tommudd]

Here is what I have always used to convert when you are dealing with inch-lbs and foot-lbs.
simple solution but one that can be important if you need to make a quick conversion.

Torque wrench conversion method
If you want to convert inch-lbs to foot-lbs, you take the inch-lb number and divide it by 12. Likewise, if you want to convert foot-lbs to inch-lbs, you simply take the foot-lb number and multiply it by 12.

EXAMPLE :

INCH - LBS FOOT - LBS
12........................1

120..............10

1200..,,,,,.....100

2400...........200

 

[Shankster]

tommudd - I'd suggest you go back and read (carefully) the posts you're responding to. You're skimming and not actually grasping what's being said.

 

[Shankster]

Just checked the FSM. The minimum pinion nut torque is 210 ft lb, thats why I bought a new torque wrench. I torqued it to 210 and that did nothing, so I maxed it out at 250. Once that did nothing I moved on to the floor jack and breaker bars. The pinion flange holder I bought from bleepin Jeep worked great.

Thanks, hopefully there was just something weird going on with your install? I'm not sure my cheap ass Harbor Freight tools would stand up to those kind of torques.

I just ordered a Yukon Gear master rebuild kit - made sure the Timken bearings were US made. It also comes with 2 crush washers so I'm allowed to screw it up once. Also ordered a Powertrax Grip Pro LSD (Torsen style) so have a good workout coming in a week or so.

 

[tommudd]

tommudd - I'd suggest you go back and read (carefully) the posts you're responding to. You're skimming and not actually grasping what's being said.

LOL I did and I am , just posting what others are missing when they think they have to have every tool that is made to do a rather simple job

Jeepster was saying you HAVE to have a 1/4 inch drive torque wrench
But you do not, you can do it without a 1/4 inch drive
I've done it at least 45-50 times over the years using a 1/2 inch and no issues in 8.25s
Many times people read what is printed in some manual and think what they read is the only way and you must do it that way or Rome will burn to the ground.
I grew up in an era where you either made what you needed or you figured it out another way that actually worked way better than " .................................. "
Too many times anymore people do not use their heads except for a hat rack
Sorry but that is just the way it is
Man I so wish the old timers I grew up around when I was in my 20s-early 30s and they were my age now could read some stuff on these forums, they'd laugh their butts off sitting around the old pot belly wood stove

 

[JeepJeepster]

Thanks, hopefully there was just something weird going on with your install? I'm not sure my cheap ass Harbor Freight tools would stand up to those kind of torques.

I just ordered a Yukon Gear master rebuild kit - made sure the Timken bearings were US made. It also comes with 2 crush washers so I'm allowed to screw it up once. Also ordered a Powertrax Grip Pro LSD (Torsen style) so have a good workout coming in a week or so.

I was installing new gears and noticed the new koyo outer pinion bearing was very tight. When I removed the factory pinion, the outer bearing was just snug. That plus having to get that initial crush of the sleeve is what made for the struggle.

Hopefully since youre reusing the factory pinion and using timken bearings, you wont have the issues I had when crushing the new sleeve.

 

[Shankster]

I've done it at least 45-50 times over the years using a 1/2 inch and no issues in 8.25s

It's my turn to LOL - I think it's hilarious that you think you can use a 1/2" torque wrench to (accurately) measure 1 ft lb of rotational resistance.

 

[Shankster]

Jeepster was saying you HAVE to have a 1/4 inch drive torque wrench

Jeepstser said nothing of the sort - this is what he actually said:

"I used a 1/4" beam style torque wrench on my pinion, worked perfect. You must use a beam style or dial torque wrench for this, no other way to do it."

I believe that his point was that you can't use a "click" type torque wrench - a 100% accurate statement. See, there you go again not actually reading other people's posts.

 

[tommudd]

LOL oh well I stand by my case and know several Mechanics ( oh wait Techs are what they are called now ) that never use a 1/4 inch , and you can use a 1/2 inch
Done it hundreds of times
This is like reading in the KJ manuals that are sent to dealerships on how to remove a front diff
Of which I own full sets bought directly from dealerships (with mechanic's notes/ shortcuts written in them )
If you read it calls for about 6 hours and removing the right LCA etc
But in doing swaps I can do it in 2 or so , can replace both front and rear diffs in less time that the " expert professional's " think it takes for just the front
I just think it is funny as all get out
I used to love to debate and always was first in class in college, but it is not a challenge anymore, since people twist and do not read or fully understand
Now I am done, have a good life reading ......................................................................................

 

[tommudd]

Oh no no " clickers " see who is not reading now
Only ones I use are beam style and ones with LED readouts, so NO CLICKERS

 

[Shankster]

Oh no no " clickers " see who is not reading now
Only ones I use are beam style and ones with LED readouts, so NO CLICKERS

I never said you used "clickers". Jeepster advocated using a beam or dial style, and I took that to mean "don't use a clicker". What you somehow got out of Jeepster's statement was that "you HAVE to have a 1/4 inch drive torque wrench" (that is a quote, from you) - which is not what Jeepster said. My only point was that you misrepresented what Jeepster said.

Here is my statement, and any good mechanic would agree - the right tool for the application in question is a 1/4" beam (or dial) style torque wrench. The wrong tool for the job is a 1/2 torque wrench (of any style).

I still don't think you understand what we're discussing here.

Oh, and you've said twice now "I am done" - you've already wrecked this string and I'm unlikely to get any more help since I doubt anyone else wants to get into this nonsensical, garbage discussion you managed to steer it to. So please, keep your word and be done!!

 

[Big Al]

You said the pin holding the spider gears in place has play, what do you think is worn, the pin or cast casing.
I'm thinking you may need a new case that the pin goes in.

Also, where did you get all your parts from, can you share part numbers too.

Mine whines like yours does and needs attention too.
I own a stock LSD too

I know when I changed my diff oil last year, my spider and side gears are spalling and destructively pitted. The crown and pinion look in excellent shape.

You also need a tool made up to adjust the casing bearings. Seen a guy make up the tool using a pipe reducer bushing 1-1/2"-1/2"
Need 2 of them and a 1/2" NPT pipe long enough to go where the axles go in.
Then he used a 1-1/2" socket to turn it with.

 

[Shankster]

You said the pin holding the spider gears in place has play, what do you think is worn, the pin or cast casing.
I'm thinking you may need a new case that the pin goes in.

Also, where did you get all your parts from, can you share part numbers too.

Mine whines like yours does and needs attention too.
I own a stock LSD too

I know when I changed my diff oil last year, my spider and side gears are spalling and destructively pitted. The crown and pinion look in excellent shape.

You also need a tool made up to adjust the casing bearings. Seen a guy make up the tool using a pipe reducer bushing 1-1/2"-1/2"
Need 2 of them and a 1/2" NPT pipe long enough to go where the axles go in.
Then he used a 1-1/2" socket to turn it with.

I don't know if it's the pin or the case that's worn or if they used the wrong pin? It's all going in the recycle dumpster at work anyway since the new pre-assembled LSD replaces the carrier and spider gear assembly. My spider gears actually looked good but I suppose looks can be deceiving.

It sounds like you have an open diff currently, not a LSD.

I just got these parts yesterday: (both from eBay)
Powertrax Grip Pro GT308229 LSD - $495 (from drivetrainlasvegas)
Yukon Gear & Axle YK C8.25-B Master Overhaul Kit - $109 (from some guy who bought the wrong kit)

The Powertrax is a beautiful looking piece of kit - hopefully it works as well as advertised. It is a helical gear or Torsen type so doesn't wear out like a clutch style LSD. The extra $150 seemed worth it. I have a Mazda Miata race car with a Torsen and it has taken a beating (140k miles) and still works perfect. The clutch style ones in the Miata seem to last 15 - 20k in that application when abused - anyway, that's my limited experience with LSDs that helped me make my decision.

The Yukon Gear kit has Timken, made in the US bearings, and an extra crush sleeve and I don't see a weak point in there.

That's funny about the tool - I saw the same youtube video and made it up last weekend. Except that I got one 1" x 1/2" bushing and one 3/4" x 1/2" bushing. I don't have a 1-1/2" or 35mm socket and the (cheaper, yeah!) 3/4" bushing has a 30mm hex. I did have to shorten the length of the 3/4" bushing (bench grinder) so that it would fit in my non-deep 30mm socket. Not sure if I need to grind down the 1"x1/2" bushing the same way to engage with the adjuster? We'll see I guess. I don't have a welder so I just cranked the fittings together super tight which should be more that adequate. I think I spent like $17 on fittings at Home Depot - I thought it would be cheaper and turns out I could have bought the actual tool off eBay for about the same. Oh well, I'll have some fittings available for my next plumbing project.

Another tool I plan to borrow from Autozone or O'Reilly's is a Bearing Race / Bushing / Seal Driver Set.

And hopefully a buddy will let me use his press to press on the bearings.

I bought a cheap dial indicator and magnetic base off eBay that seems to work well.

And then there's the seemingly controversial? 1/4" beam style torque wrench I'll borrow from another buddy to gauge the pinion bearing preload.

I think that's it? Tentatively planning to do it this weekend so can report back my successes and failures. The plan is to do it solo but the 1/4" torque wrench guy needs to do his 4Runner diff too at some time so I may have another set of hands.

 

[Big Al]

Well, I guess your info on what you bought is a different path on what I'm heading down. I need new spider, side gears and clutch discs and steel plates for my rear end.
I also like what you bought. Had a look on the web and it's hard to see what Powertrax is using in place of the clutch discs.
I tried to source parts from Yukon gear, but only finding parts for thier open differential gears.

I have a LSD in which Jeep calls it a 8.25" trac loc.
Do you currently have a trac loc?

 

[Shankster]

Well, I guess your info on what you bought is a different path on what I'm heading down. I need new spider, side gears and clutch discs and steel plates for my rear end.
I also like what you bought. Had a look on the web and it's hard to see what Powertrax is using in place of the clutch discs.
I tried to source parts from Yukon gear, but only finding parts for thier open differential gears.

I have a LSD in which Jeep calls it a 8.25" trac loc.
Do you currently have a trac loc?

I don't have a trac loc, I have the standard open differential (i.e. worthless off road, deep snow or where one side is on ice and the other on pavement).

The Powertrax Grip Pro has helical gears or in other words a Torsen style LSD. It's really clever and much better than clutches in my opinion. I think the other similar one I was looking at was the Eaton Detroit Truetrac (don't recall the part #) which is tried and true with an excellent reputation but a few hundred bucks more expensive. I didn't see any reviews on the Powertrax for that part # but saw a bunch of glowing reviews for different vehicles so decided to go for it.

 

[Shankster]

So it was a bad day.

I did figure out why my center pin was loose - the retaining pin/bolt was sheared near the end of the short threaded part. What's amazing (and made my day at the time) was that when I backed out the 3/8" long part with the hex on the end, the long (1.5") broken piece came with it. The slight angle to the broken ends must have made contact and the 1 or 2 threads left on the long piece followed the threads on the short piece. I was able to use a center punch to rotate it out for the last couple of rotations. So the center pin was just loosely held on the one side and allowed to move a bit and start some wear on the carrier casting. Probably only a matter of time before the pin broke on the other end and left me without (rear) drive, or the spider gears got out of sync which would make for a much more exciting failure.

Where things went downhill was when I tried to remove the ring gear - all but one of the 10 bolts broke inside the ring gear and the one that didn't had destroyed threads. I figure whoever rebuilt it after its earlier catastrophic failure either reused the old torque to yield bolts, over torqued, or somehow managed to muscle in bolts with the wrong threads (I know there are metric and a SAE versions - I wouldn't have thought it possible to mix them up but who knows).

So I'm not going to mess with trying to drill and easy-out the bolt ends - don't have the time or the bucket of drill bits and based on the condition of the threads in the one I got out I'd be tapping them all and the chances of success on one hole seem slim, let alone 10. Shopping for new ring and pinion now.

When I assessed the condition of the pinion bearing it seemed in perfect shape - silky smooth with a bit of resistance and no play. My short lived plan was to leave it be and I think it would have been fine. I'll work on getting it out over the next week, but pretty deflated right now so don't have the enthusiasm.

My Libby will be on jack stands for another week or 2 unfortunately. I guess I need to work on something else for a while - PlastiDipping the wheels maybe?

 

[Big Al]

Great to hear almost everything went well. Now the 1 out of ten bolts that didn't shear, do you have thread gauge to check if it's metric or standard.
Did it look like the previous rebuilder used loctite.
Maybe he used non-removeable loctite (red) thought it was the removable (blue) loctite.
Any signs of loctite on the thread of the 1 good bolt.

Maybe the previous guy thought they were right hand thread at first and then stretched them like you mentioned. Haven't worked on mine yet, but most posts say they are left hand thread holding the crown-(bevel) gear onto the carrier.

 

[Shankster]

Great to hear almost everything went well. Now the 1 out of ten bolts that didn't shear, do you have thread gauge to check if it's metric or standard.
Did it look like the previous rebuilder used loctite.
Maybe he used non-removeable loctite (red) thought it was the removable (blue) loctite.
Any signs of loctite on the thread of the 1 good bolt.

Maybe the previous guy thought they were right hand thread at first and then stretched them like you mentioned. Haven't worked on mine yet, but most posts say they are left hand thread holding the crown-(bevel) gear onto the carrier.

Oh crap, left hand threads? I almost hate to look now. I tried to back them out as if they were RH. That would explain it though, and yours truly would be 100% responsible for destroying his perfectly good ring gear. One of those jobs you don't pull out the manual for because it seems so obvious!

 

[Shankster]

Yep, verified LH threads F$%^!!! I'm an idiot!

Knowing that I was able to back out 2 of the bolts really easily with a center punch. I'm sure I could get the others in less than an hour. In the one that came out originally I picked out a bunch of the metal and the threads don't look completely hopeless but could only screw a new bolt in about half way - I would need to tap that one hole for sure but I think I could save it. Where the hell would I find a left hand tap? Not sure what the thread is - I measured 12 threads in 13mm so it's probably SAE. Time for bed so will do some research in the morning.

 

[Shankster]

Looks like threads are 3/8-24 and LH taps are readily available, at least on line. I may saunter down to Ace Hardware and see what they've got before I order anything.

Thanks Big Al, assuming I can save this ring gear you just saved me $200+