George's 2003 Sub "lucky7"

[Georgeb]

Hey Guys it’s been a while. I have been a busy boy lately so not on here much. I am in need of some guidance. I noticed a couple drops of gear oil on the floor of the shop so I investigated and found it coming from the rear pinion. I picked up a seal and dove under it today. It turns out it is leaking through the splines not by the seal. I marked the pinion, nut and yolk and pulled the yolk off. The nut came off pretty easily. The lube that drained to the pan had a metalic sheen to it. I installed a new pinion seal and reassembled everything. At first I tightened the pinion nut a little past the original position but it seemed to be too tight of a preload and required quite a bit of force to turn so I backed it off to just a hair tighter than it was according to the marks I made. I fear there is an issue with the pinion bearings. My question is, can I change bothe pinion bearings and races, use the original shims and install a new crush sleeve and be ok? Or, will it be necessary to reset the pinion depth and gear lash/mesh?

 

[Honky Kong jr]

The main thing your gonna run into is gear mesh either way you do it the ring and pinion contact area is gonna change to where it was. If that makes sense. If you do change them use Timkin or SKF not the National stuff they are Chinese or India made but I’d rather have India then Chinese bearings but any way the pinion bearings are pretty critical and you just want good parts in there.

 

[Georgeb]

The main thing your gonna run into is gear mesh either way you do it the ring and pinion contact area is gonna change to where it was. If that makes sense. If you do change them use Timkin or SKF not the National stuff they are Chinese or India made but I’d rather have India then Chinese bearings but any way the pinion bearings are pretty critical and you just want good parts in there.

I understand but how much will it change if I use the same shims? I hear of guys using a setup bearing which has the inner race diameter opened up so it slips on and off the pinion and then using a different new bearing for final assembly. Seems there could be a risk of a difference in pinion depth when doing that too.

 

[Honky Kong jr]

I understand but how much will it change if I use the same shims? I hear of guys using a setup bearing which has the inner race diameter opened up so it slips on and off the pinion and then using a different new bearing for final assembly. Seems there could be a risk of a difference in pinion depth when doing that too.

That’s the way I did my 12 bolt and my front 10 bolt. Mine isn’t a daily just keep an eye on your pattern with the marking compound. Drain it clean the ring gear and apply compound rotate and take a pic then disassemble do your repairs and recheck and compare the two.

 

[74 Shortbed]

The new bearing is the same thickness as the mock up bearing regardless of MFG, if it's not the new bearing is bad and needs to be exchanged..

 

[Georgeb]

That’s the way I did my 12 bolt and my front 10 bolt. Mine isn’t a daily just keep an eye on your pattern with the marking compound. Drain it clean the ring gear and apply compound rotate and take a pic then disassemble do your repairs and recheck and compare the two.

I’m tempted to do this. Mine is a daily driver and I don’t have backup. I am not against doing additional setup But I don’t have the tools.

 

[Georgeb]

The new bearing is the same thickness as the mock up bearing regardless of MFG, if it's not the new bearing is bad and needs to be exchanged..

Am I correct in my understanding that regardless of manufacture the bearings should be within a couple thousandths of each other size wise? So the shims under the one in there now should set the pinion at the correct depth in the housing when using a new bearing?

 

[Honky Kong jr]

I’m tempted to do this. Mine is a daily driver and I don’t have backup. I am not against doing additional setup But I don’t have the tools.

I think most stuff can be rented. I made my bar for holding the yoke to set preload. If you take it somewhere to have it done and it turns into a whiney bitch it’s on them. I’m gonna guess a lot of shops won’t touch it with out doing both pinion and carrier bearings and do a total reset. Well decent shops anyway. Open it up and screen the fluid see what you get.

 

[74 Shortbed]

Am I correct in my understanding that regardless of manufacture the bearings should be within a couple thousandths of each other size wise? So the shims under the one in there now should set the pinion at the correct depth in the housing when using a new bearing?

Bearings are a standard pretty much world wide and all use the same part numbers and all dimensions are the same, but like anything else you always measure to confirm..

 

[Georgeb]

I guess I am going to go back under this thing and inspect that front bearing. I am also going to catch he drained lube in a glass container so I can look at it more closely. I will need another seal. I should have looked at it before I replaced the seal yesterday. It was basically in my hand. If I confirm metal particles in the lube I will pick up a bearing kit and rebuild it I guess.

 

[74 Shortbed]

Forgot to mention, there is one bearing MFG not consistent with the rest, but don't remember the name since I only got bearings from them twice over 25yrs and it's not a name you hear everyday, both times the thickness was off by a few thousands, enough that I took them back..

 

[Georgeb]

Well, I don’t know.... I pulled the drive flange off again, knocked the seal off and cought all the fluid that came out in a clean pan. The front pinion bearing is perfect and the race looks good too. There are no large metal shavings in the fluid. If I swish the fluid around in my shallow drain pan I can see a sort of metallic sheen that looks about the same as when you swish a dirty auto trans pan with fluid in it. This truck has a G80 govlock and I cause it to engage rather often in the snow, gravel, mud and wet pavement. I wonder if what I see is in the fluid the friction material? Anyway, it’s back together and I am comfortable with it. It will become obvouse if there is an issue lurking in there.

 

[74 Shortbed]

From what you're saying it all sounds good to me, I'd be running it..

 

[Honky Kong jr]

From what you're saying it all sounds good to me, I'd be running it..

I think that’s what he’s gonna do..

 

[74 Shortbed]

I think that’s what he’s gonna do..

Yep, sounds like it..