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Air Randy
03-28-2011, 10:01 PM
A certain individual approached me to help him install an ARB and new gear set into his spare 80 housing. Said individual unfortunately decided to "help" by disassembling the entire 3rd member, failing to mark the bearing caps L or R, and throwing away the stock pinion/carrier/ring gear without bothering to determine the size of the oem shim pack under the pinion bearing. :rolleyes:

To save me having to take this thing apart 20 times doing trial & error on getting the pinion depth set correctly, does anyone know what a good starting point would be for the thickness of the shim pack?

Romer
03-28-2011, 10:03 PM
why did you let Kevin into your shop :D

Robbie or Ben Ashcraft could probably give you the best guess

Dr. Schlegs
03-28-2011, 10:27 PM
I bet the bearing caps are marked. I would venture to say that one set has two dots punched to denote left from right. That is of course from me never seeing it before.

I bet said individual is very grateful for Randy's help and would love to learn how one sets up gears and an ARB locker. I bet they heard Ricardo talk about how he didn't know righty tighty lefty loosy, before he met you Randy.

RicardoJM
03-28-2011, 10:40 PM
... I bet they heard Ricardo talk about how he didn't know righty tighty lefty loosy, before he met you Randy. ...

For an individual who makes their living listening, I am a bit disappointed in said individual's recollection. I definitely knew it was righty tighty lefty loosy before meeting Randy however it took an apprenticeship mentored by Randy to finally get me to where I no longer have to pantomime it every time I put a wrench on a bolt/nut. :D

Oh and on the topic, I'm of no help on picking a reasonable starting point.

coax
03-28-2011, 11:08 PM
Not sure if this is helpful, but there are tons of gear writeups on Zuk's website that may give a rough estimate of what would be needed.

http://gearinstalls.com/

Air Randy
03-28-2011, 11:29 PM
I think a good starting point will be .080. You can assemble the pinion into the housing using that shim size to start with. Then if you torque the pinion nut to 150 ft lbs you can check the preload on the pinion without a crush sleeve in place. If you are below 8 inch lbs you add shims in .002 increments or remove shims if you are above it. This will get you close, then you assemble the carrier and verify it using the tooth pattern method.

Kevin - Two things:

1-My inch pound torque wrench is dead. You need to get an inch pound beam or dial type torque wrench. The dial type are better but pretty expensive. A KD tools 2956 beam type wrench works OK and is fairly reasonable. This must then be donated to the shop for the betterment of others. This is the price you must pay grasshoppa for failing to keep the oem pinion shim. :D

2-Romer was just guessing, if you hadn't said anything no one would've ever known we were talking about you :rolleyes:

AxleIke
03-29-2011, 12:01 AM
Randy, sometimes the gears are marked with the pinion shim numbers, usually scribed into the head of the pinion. They are a good starting point.

If not, your plan of .080 is a good one. Best of luck!

Air Randy
03-29-2011, 11:51 AM
Randy, sometimes the gears are marked with the pinion shim numbers, usually scribed into the head of the pinion. They are a good starting point.

If not, your plan of .080 is a good one. Best of luck!

Usually the numbers scribed there are the backlash the gears were set to during testing at the factory(.008 in this case), and the CD distance. The CD (centering distance) distance (2.371" scribed on Kevin's gears) is the distance from the bottom of the pinion to the exact center of the ring gear used for factory setup, when it's all installed. You have to have a lot of special tools to measure it that way.

FJBRADY
03-29-2011, 12:11 PM
Said individual unfortunately decided to "help" by disassembling the entire 3rd member, failing to mark the bearing caps L or R, and throwing away the stock pinion/carrier/ring gear without bothering to determine the size of the oem shim pack under the pinion bearing. :rolleyes:



:ranger::gaah::ranger:

powderpig
03-29-2011, 12:15 PM
If it is the rear differential, the rear pinion shim is usually around .050(old ones that I remove are typically this thick) when i remove to install lower gear ratio gear sets. As for the bearing caps, good luck on that one fit hey are not marked. One way to make sure is to loosely install the bearing caps and see if the threads will line up easily, and the adjusting nuts will work easily.
As for putting 150 lbs of torque on the bearing with out the crush sleeve, I would bet that the bearings are going to reach a preload with a lot less force.

What gear ratio is one using? What brand of gears are you using. I did not read the orginal post that well and commented on something that does not pertain.
More information is better than not enough.

Dr. Schlegs
03-29-2011, 01:11 PM
If I remember correctly from my last visit to Randy's to help him bleed his brakes, they are Nitro 4.88's. Not that they are mine I just saw them glistening in the warm glow of fluorescent lighting. :D

Air Randy
03-29-2011, 01:32 PM
If it is the rear differential, the rear pinion shim is usually around .050(old ones that I remove are typically this thick) when i remove to install lower gear ratio gear sets. As for the bearing caps, good luck on that one fit hey are not marked. One way to make sure is to loosely install the bearing caps and see if the threads will line up easily, and the adjusting nuts will work easily.
As for putting 150 lbs of torque on the bearing with out the crush sleeve, I would bet that the bearings are going to reach a preload with a lot less force.

What gear ratio is one using? What brand of gears are you using. I did not read the orginal post that well and commented on something that does not pertain.
More information is better than not enough.

If it is the rear differential, the rear pinion shim is usually around .050(old ones that I remove are typically this thick) when i remove to install lower gear ratio gear sets. WHAT IF IT IS A FRONT DIFF? ANY GUESS ON SHIM SIZE?

As for the bearing caps, good luck on that one fit hey are not marked. One way to make sure is to loosely install the bearing caps and see if the threads will line up easily, and the adjusting nuts will work easily. AGREED

As for putting 150 lbs of torque on the bearing with out the crush sleeve, I would bet that the bearings are going to reach a preload with a lot less force. AGREED

What gear ratio is one using? What brand of gears are you using. 4.88 NITROS
[/QUOTE]

Air Randy
03-29-2011, 01:35 PM
from my last visit to Randy's to help him bleed his brakes

To be clear, said individual just showed up (probably to mooch something from me) and I happened to put him to work pumping the pedal (which he is qualified to do) instead of hooking up the power bleeder. :D

Dr. Schlegs
03-29-2011, 01:50 PM
When was Tom over to your place?:p:

Air Randy
03-29-2011, 02:07 PM
When was Tom over to your place?:p:

Hey, I left out the part about it taking me longer to explain the pump-hold-release-pump cycle to you than it would have taken to hookup the power bleeder :D Leave poor old Tom out of this

FJBRADY
03-29-2011, 02:25 PM
Hey, Leave poor old Tom out of this

:thumb:

powderpig
03-29-2011, 03:59 PM
Stock pinion shim for the front is close to .070.
This only works if you have the same koyo bearing that came out of the diff from the factory.
As for the kits that JT sells. some time they sub different bearing, but are close to the same bearing. This can some times add to the equation. Some of the pinion bearing have been thicker than stock, thus needing to some math to figure out the right shim or group of shims to make it work.
good luck

Air Randy
03-29-2011, 04:46 PM
Thanks Robbie :bowdown::bowdown::bowdown:

.050 in the rear and .070 in front for starting points.

RockRunner
03-29-2011, 05:38 PM
Hey, I left out the part about it taking me longer to explain the pump-hold-release-pump cycle to you than it would have taken to hookup the power bleeder :D Leave poor old Tom out of this

Yeah what he said.......................now pump boy pump!!!:D