Assessing the damage.

[Jay Tabor]

NO COMMENT!

dont worry about backlash
most importante is the pinion gear depth and preload.
period.
end of discussion
terminado

the backlash thingy:
is a range of say .006" to .009" [THATS JUST AN EXAMPLE DONT BANDY IT ABOUT AS DANA SPECS FOR GOODNESS SAKES]
SO the carrier pigeon is different..
ok, ............................
whats that got to do with anything?
take the same carrier shims and replace them behind the same carrier pigeon bearings [or is that bering sea?]
toss the carrier and bearings into the housing [this is where it gets fun fun fun !!!]
slam the beringsea caps back on the carrier bearings, tighten them to some huge amount of newton meters,
then slap yer ten dollar dialing for dollars indicator on the ringostar gear and hopefully you gots it set right,
so's it dont move around none [nun] when you be checking backlash.
then rock that ring gear back and forth.. watch that dial indicator indicate.
write that amount of indication down. MARK THE TOOTH you measure it at.
if the backlash is in the middle of the range keep going, if it isnt- as in way too much or way too little, then remove the carrier and swap shims from behnd the carrier bearings and try try again.
then resume here>>
slide that indicator outa the way, turns that ringostar gear 180* [NOT TEETH]
MEASURE the backlash at that tooth,WRITE IT DOWN.
compare.. are them two measure ments exactly the same-o? if so keep going.
if not, better find out why, a range of about .001"+- in backlash difference is ok in 360 of ring gear.
mark that tooth.
you better hope they are the same backlash . . or theres gonna be twouble! in this case its probably the new carrier not the ring gear fault less of course you let a grain of sand get under the ring gear when you mounted it.
ok rotate the gear 90*[NOT TEETH] and measure the bad boy, make notes mark the tooth
, rotate 180* [you getting the hang of this yet"??}
measure backlashings take notes, mark the tooth.
ok ARE ALL 4 OF THEM MEASUREMENTS THE SAME?
COMPARE THE BACKLASH WITH THE DANA SPECS FOR THAT MAKE MODEL COLOR OF AXLE.
if its all - .008" and thats within the specs the publication has.. THEN JUMP FOR JOY!!
YELL YAHOOOOOOOOOOOOOOOOOO!! I DID IT!!
LOUD AS YOU CAN!
nows when you put on the real bearings and double check back lash, using same teeth marked before and hopefully get same measureents.
ok then paste your white lead on ALL the ring gear teef, since its your very very very first time . .
do all the teef. its fun . . you enjoy grafitti anyways, nows yer chance!
hold tight to the ring gear as you turn the pinion yoke, rotate that ring gear once around the whole thing . . then turns her the other way -like yer backing up, make sure you be holding the ring gear tight while turning- you get better smear of the white lead better more.
ok then whip out yer teef mark chart that the dentist gave you, and look for cavities and proper gear pattern . .
the cheating way to do it, is remove some of the lead off of the drive side [convex side of the tooth] compare the smear of lead to the shiny wear marks on the ring tooth, notice if the pattern is same exactly where the heel and toe start and finish and where the depth of the pinion gear is on the ring gear tooth. see if the shiny original wear marks are same as the whitelead smear marks on the other teeth.
[thats advanced smart mechainics cheat sheet way of doing things, so itll cost you for me to reveal that secret of the gear mesh society]
if all the pattern is the same all the way around on both sides of the ring gear,
dont ferget to look at the lead smear on the opinionated gear also . . .
and the reverse side cancave for pattern.
then you be cruising.
then you get to jump up and yell YAHOOOOOOOOOOOOOOO I DID IT! REAL LOUD . . one more time.
WATCH THAT TOW HITCH WHEN YOU JUMP UP!
I check the backlash first thing, if its not right- no sense at all checking the mesh pattern [ i eye that at same time anyways but thats advanced techniques].
so adjust backlash because gear mesh pattern is depending on backlash to be correct or gear pattern will be off.
thats why i dont care what the old backlash was, if you have it fine, if not its easily obtainable anyways and theres a range of backlash to be within, so its no where near as critical as the pinion depth or preload is.
I set the backlash at the larger end, why have .005" when you can have .010"?
that gets more oil in between the teeth= cooler running, less abrasive wear on the teeth anyways.
pinion depth causes more singing and moaning than backlash does from my experience[s].

I do a bunch of gear mesh patterns and check all the teeth to make sure its same everywhere, it usually will be if the backlash is same.
after its all set up and adjusted i wipe off the white lead, some folks leave it on,
i dont want any possibility of dirt contamination to them fancy new gears and positraction diff!
I rotate the ring gear a few times and double check back lash just to be sure.
double check the bearing cap bolt torque- they get loctite too.
then slap on the cover and bless it . fill er with oil [ and sawdust to quiet them howling gears;JUST KIDDING]
ANOTHER fast set up procedure is i take the old carrier bearing races and grind out the ID of the inner race just enough so the bearing hand fits onto the carrier bearing support snout -snugger the better, and use them as set up backlash bearings, I prefer them to a fake set up bearing and race-just incase the measurements are off. saves pulling it apart two more times.
once the backlash is adjusted, i slide off the set up old bearings, dont mess up the shim packs at all clean em good of dirt, press on the new carrier bearings, toss it back in and check endplay. its usually the exact same, so proper torque and loctite on bearing cap bolts with the caps and mating surfaces being super clean- I button it up.
one trouble with dana housings is the carrier bearing shim pack has a built in preload in it to make the carrier fit real tight into the housing, its a real pain to place and remove the carrier a bunch of times [easier on the bench than under a vehicle] thats where the case spreader comes in handy-long as you dont spread the case too much.

[RobertC]

There is no backlash measurement to duplicate.

From what I learned from watching my mechanic set up a differential (non-IH - 30 years ago):

The backlash should not be "lower" than the low end of the range specified in the shop manual -- shows .005 - .009. (from a T/A manual - use the spec in your Scout manual)

So, you should not measure lower than .005 in any spot in a full rotation of the gear.

It is ok if it is over the high limit...

This was the case for the differential he set up --- the differential now has 190,000 miles on it.

[jauringer]

Great info! Thank you.

Now, I'm ready to move forward.... Wait, where is my carrier Oh yeah, I don't know

Well at least I'll be ready when that time comes.

Jason

[Jay Tabor]

seriously-- most times I, others when rebuilding/setting up a diff, in the shops I worked at/in would just rock the ring gear, revolve it-rock the ring gear ... check the back lash by feel, doing it so much and so often, I got a good touch for feeling the backlash by hand.
sure id stick a dial indicator on to double check. it agreed with me..

[jauringer]

very, very bored today. rainy, cold and the project is at a stand still. I just basically looked for anything to do in the garage.

Blasted and powder coated the diff cover and U-bolts.



I also installed the fitting for a breather that I tapped in the very beginning of this project. I might have forgotten to mention that. I've got some braided SS line that will go up to some point on the underside of the body to a little breather. I may "T" it into my TC breather as well. I haven't decided yet.



Also received my fluids yesterday. If you read the gear oil article I posted in this thread, it's obvious why I chose to use the Amsoil Severe Gear.



That's all I could find to do so afterwards I took a nap.

Jason

[Jay Tabor]

run the hose for the axle breather up to the engine air cleaner housing.
filtered air is the best!

[ziggybock]

Jason,

Are those new Ubolts or are those the ones you pulled off the axle? It is hard to tell in the picture but the threads look like they are used.

[Dennis Bernth]

Originally Posted by jauringer

very, very bored today. rainy, cold and the project is at a stand still. I just basically looked for anything to do in the garage.

Blasted and powder coated the diff cover and U-bolts.



I also installed the fitting for a breather that I tapped in the very beginning of this project. I might have forgotten to mention that. I've got some braided SS line that will go up to some point on the underside of the body to a little breather. I may "T" it into my TC breather as well. I haven't decided yet.



Also received my fluids yesterday. If you read the gear oil article I posted in this thread, it's obvious why I chose to use the Amsoil Severe Gear.



That's all I could find to do so afterwards I took a nap.

Jason

Your mileage may vary, but I used the exact same LS additive in my 79 Scout II with a Powerlok and had issues with the clutches being 'grabby' on turns. At the recommendation of a buddy that has rebuilt a lot of diffs, I got Mopar LS additive at the Chrysler dealer, added that, and problem solved. He said the aftermarket additives just are not as good as the OEM stuff. I've found that I agree that the dealer LS additives are better than the stuff sold at the chain auto parts stores, at least when I've had issues it's always been with the 'aftermarket' additive, never with the Mopar stuff.

[db1115]

I thought the amsoil didnt required a ls additive.

[jauringer]

Dennis, that's very good to know. Apparently, the Auburn comes with it's own additive but I would like to save that one until after the 500 mile flush, so I need to come up with something in the mean time. I'll call the Chrysler dealer here local and grab a bottle. Thanks for saving me the trouble!

Davis, I don't think that's correct. The back of the bottle recommends Amsoil Slip-lock additive in the event chatter occurs. I'm going to do some more reading.


*Edit* Found info pretty quick but I'll see what else I can find.
Severe gear does include some friction modifier. Additive is dependent on the situation as the amount included is minimal so it looks like results will vary.

Thread 1

Thread 2 - Of course I'll get a different opinion on every thread.

Amsoil.com

Considering the above, it might be a good idea to have a bottle of slip lock around in the event I get chatter but it may not be necessary.

Note from Amsoil on Slip Lock -

NOTE: AMSOIL Synthetic Gear Lubes do not require the use of this additive. However, not all differentials respond the same and if chatter is noticed, the addition of AMSOIL Slip Lock will eliminate it. For chattering differentials not running AMSOIL Gear Lube, this product is an excellent solution to the problem.

Mixing with other additives:

Aftermarket oil additives, other than those specified by AMSOIL, are not recommended for use with AMSOIL gear oil.

AMSOIL Severe Gear is compatible with most limited-slip differentials. If limited-slip differential chatter occurs, add AMSOIL Slip-Lock™ friction modifier additive

Jason