Operation- harlan run

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

SFROMAN

SFROMAN

SILVER Star
10 Year 15 Year
Joined
Jun 30, 2009
Threads
133
Messages
3,197
I decided to start a thread where I can gather info and keep it consolidated to make it easier on me to track as well as it could help others in the future to have any info that is gathered consolidated into one thread. (I plan to ask quite a few questions)

SITUATION- Broken pinion on rear differential on my FJ40.

MISSION- To make necessary repairs as well as any upgrades to render my FJ40 drivable in order to make the Harlan next month

EXECUTION- hopefully I can get a hand from some of the members in order to save time and money.

I need to match the 4.10 gears on my front axle. Ramon found a third member for me on the classifieds with fine spline axles I will be contacting the guy shortly.

So is it just a matter of removing all the old stuff and replacing it with the new? Will I need any special tools to do this?

I am going to search and hopefully I can find torque specs and or a step by step thread that I can follow.

I would still need some help with the installation from someone with a little more experience though.

I will post up picks of the carnage in a little bit.
heres the pics of the damage.








Any info, recomendations, comments, suggestions are more than welcome.

Thanks
DEL
 
Last edited:
Darren,
I will keep you posted.
You like my OPORD format? Couldnt help myself haha.

Do you know where I can find metal tubing for my Antiwrap bar near us?
Based on the info I got from Ruffstuf FAB. I am gong to be using 2" tubing with
1/4 " wall.
 
Del, the beauty of the Cruiser axles is the third member is a whole unit. In the rear, all you have to do is pull the spider gears from the rear (this is already done on your truck on the trail :) ) , remove the c-clips, pull the inners out a few inches, and pull the third member out from the front.

The ring and pinion is already setup if you buy the whole third member (assuming the po didn't monkey around with it) and all you have to do is drop it in, install the inner axles, c-clips, spider gears (good time to throw in a locker if you don't have one in there already) and button 'er up. I pulled my front third for my ARB install and there are no clips in the front, so I only had to pull the inners and break pull the third out. Took me longer to break the OE seal on that puppy than anything else, but now I know the trick :)

https://forum.ih8mud.com/40-55-series-tech/214638-help-removing-rear-third-member.html

:beer: R
 
I know there are a lot of folks with more diff experience than I, but thought I might mention this based on a discussion from Saturday afternoon... If there is any chance that the "new" 3rd is not properly setup up and nobody has the proper tools and experience to check the backlash, pattern, etc. I would suggest moving the front 3rd to the rear and placing the new 3rd in the front. It will see less use in the front and will last longer since it will only be engaged for trails. Just my 2 cents...
 
So no checking backlash and all that good stuff???
 
Currently I am waiting for a response to emails I sent to a guy on mud (thanks Ramon) and a guy on nc4x4. Hopefully I get some responses soon.
Once I purchase what I need I would love to have the new third member and my axles inspected by you Darren. I don't want to find out something was broken after installing it.
I want to install an arb air locker but @ $800 it is going to have to wait.
 
Aussie's are great in the rear - my god that sounded horrible....

Edit:
Aussie Lockers work well in the rear differential on a Crusier. Good, cheap traction that's very dependable and predictable onroad as well. Easy install.

:beer: R
 
I found a guy that claims to have 2 rear axles in charlote. Does not know the ratio to the gears though. Is there a way to figure out the ratio by looking at it. I am waiting to see what year they are from and if he sends me pictures.

I looked at the price for the ausie locker and it is definitly alot closer to my price range at about $300. I am going to wait to purchase it until I can find the parts I need first.

Darren when would be a good time for me to wing by your place? Weekdays or weekends?

I get off work early on tuesdays and wednesday due to physical therapy so I can swing by your place then.

Please let me know what works the best for you.
 
Chalk lines on the pinion and diff housing so you can count the revolutions. Chalk a line on the tire / hub so you can count revolutions. Turn the tire one complete revolution - if the pinion spins a bit less than 4 times, it's 3.73, more than 4 turns, should be 4.11. All this assumes it is factory r/p. Don't forget though, if it's 4.11, there is no guarantee it's fine spline; in fact, chances are much greater it coarse spline since '78 is the only factory 4.11 fine spline pinion.

:beer: R
 
The guy from nc4x4 got back to me and he has 2 rear axles for $100 but they are early 70. Not sure what gear they have but I understand the rotation technique with the chalk line so I might go out to pick them up. I know they are not likely to be fine spline but the guy from mud is just not responding and i dont want to run out of time.
While im on the subject of fine spline. Is it refered fine spline due to the spline on the pinion that conects to the driveshaft or is it refered fine spline due to needing fine spline axles?
 
Fine splines is easy. Look at your old pinion where the yoke goes on it and you will see there are only about 6 - 7 splines on it. A fine spline one has about 20 or so splines making it stronger.

Hope that you can understand that.
 
Ok, The Mud guy you mentioned Ramon is a bust. He has no thirds currently available.

I got my antiwrap kit in the mail yesterday. I will just need to find some metal tubing and get it welded up.

The search continues for a rear axle.
 
You must log in or register to reply here.

Share this page

Back
Top Bottom