Dana 20 rebuild.. tools needed?

[tad3790]

Hi guys,
I almost hate posting because it has probably been discussed a million times on here... but Im am not seeing the info I am looking for in any one place. So I figured maybe somebody could help me.

Mine is J shift.

I have never rebuilt a transfer case. I am thinking I have an "ailing" Dana 20. I keep hearing squeaks, and rotational rubbing sounds so I jacked up the truck and manually rolled tires over as I listened. I have ruled out the brakes and for the most part the U joints. However, I found that the rear output shaft of the transfer case to squeak and make little birdy sounds

Then I wiggled the front output shaft and found to have some axial play. It is NOT leaking... but that seems odd that I would have that much play.

I am your average recent buyer who bought a "restored" Bronco only to find out it was rebuild in a can (black spray paint) that was used in too many places. Next time I buy a Bronco I will use my X ray vision to examine these things.

My questions are the following..

1. Do I need anything special beyond a rebuild kit, regular hand tools, a press and dial indicator to do a basic rebuild?

2. I have found some of the parts available from the Bronco retailers to be a POS while others are quite nice. Are the rebuild kits (Like Tom's has) good or are there better parts available?

3. Outside of surprises like worn shafts or main gears are there any surprises I should know about during a rebuild? What should the lash be in in specific gears? Ways to tell if the internals are worn(beyond seals and bearings)

I did find the shop rebuild instructions online. It seems fairly straight forward... yet as I searched this forum I saw a few who suggested specific part numbers to buy bearings and seals "alacart" instead of buying the full kits.

Any help is appreciated!

 

[70_Steve]

1. Do I need anything special beyond a rebuild kit, regular hand tools, a press and dial indicator to do a basic rebuild?

Make sure the rebuild kit included the idler/intermediate shaft. I've never used a press for the bearings. I heat them in a toaster oven to about 250° and they drop right on. You might also want to set the rear output shaft bearings to a preload rather than an end play. Seems to help eliminate popping out of rear low. In that case you will need an inch/lb torque wrench. I used a 0-60 inch/lb beam style that I found on Ebay for about $40. Here are instructions for Wild Horses Extreme Output shaft kit to give you the idea. And yes, 2-7 in/lb is about right.
http://cdn.wildhorses4x4.com/downloads/WH/8272 08-08-06.pdf

I set the front output shaft to an endplay, but shoot for 0.001 instead of the factory 0.005.

2. I have found some of the parts available from the Bronco retailers to be a POS while others are quite nice. Are the rebuild kits (Like Tom's has) good or are there better parts available?

I've used kits from Jeff's and WH, and found them to be about the same quality. Timken bearings, etc... Also make sure you get the input shaft bearing!

3. Outside of surprises like worn shafts or main gears are there any surprises I should know about during a rebuild? What should the lash be in in specific gears? Ways to tell if the internals are worn(beyond seals and bearings)

Wear on the gears will be obvious, as these are straight-cut gears. Pay attention to the ends of the shift forks, where they rub the sliding gears

I did find the shop rebuild instructions online. It seems fairly straight forward... yet as I searched this forum I saw a few who suggested specific part numbers to buy bearings and seals "alacart" instead of buying the full kits.

All depends on what you need. The kits are way cheaper than sourcing individual pieces-parts. Here's a link to a decent Service manual that has been updated to include notes for the J-shift.
www.classicbroncos.com/dana20/dana_20_manual.html

 

[tad3790]

Thank you!

 

[Rustytruck]

Check this post.

http://classicbroncos.com/forums/showthread.php?t=207537&highlight=sealing+dana+20

 

[66BlueGoose]

A few items:
- A decent seal and race kit, this one had all the sized I have need so far for dana 20, dana 30 and 3 speed manual. OTC 4507 Bearing Race and Seal Driver Set
- Check to see if the rebuild kit you order has the "front output shim kit", if not, order one separately.
- Don't skimp on the sealant of your choice.