Welded Pinion Nut

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KY Longhunter

KY Longhunter

Joined
Aug 25, 2007
Threads
224
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3,669
Location
Bowling Green, KY
Below is a picture of my Rear Diff I recently cracked open. The PO apparently had welded the pinion shaft pin. I'm apparently going to need a whole new Third Member unless anyone has any other suggestions.

Anybody have a used Third Member in good condition?

Anybody bought parts from Cruiserparts.net ?

Thoughts?
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...mmmm, yummy. That's what years of neglect will get you. Your best option may be to simply change out the third member. What ratio do you need? I have two good thirds with 4.11:1 ratio, course spline pinions from a 08/75 FJ40. PM me if interested.
 
Just look for one with the same ratio from a later model FJ40 (1980 and up I think) or one from an FJ60 or 62. The good news is that these are not real desirable by many so they are abundant and cheap. I bought two from fronts of FJ60's (virtually no wear) for $200 locally with no freight. Post up in the wanted section. Like anything, these can be shipped but you may find one within a reasonable drive. Also seek out your local TLCA chapter to network with other cruiserheads....there's probably one nearby and cheap. Yes you do need to have both front and rear the same ratio if you intend to ever use 4WD.

If this is in the rear you are going to have to remove the pin/spacer for the spider gears. This allows the axles to be moved inward slightly to remove the C clips that hold the axles in. If it's the front buy a FSM because the proceedure to too involved to get into here.

The one you got looks real nasty. Is it broken, inoperable, noisy or are you just concerned because of its appearance? If the latter you may want to give it a couple fluid changes and run 'till ultimate failure. Can you grind off the welds to get at the pinion nut?
 
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DGangle

Im in the process of a frame off and was trying to find source of nasty leak coming from rear end when I discovered the condition of third.

I think I will go back to stock config of diff since I'm not planning on doing any serious off-roading (at this point anyway).

Found complete third member at Cruiserparts.net for $200 free shipping & handling. Will probably go that route, but may try posting in the Wanted section as well.

Thanks for the advice. AR
 
$200 is real steep for a 3.70:1 from my experience. Fine spline 4.11:1's are going for $100-125 here on mud in the past. Might not be that bad of a deal depending on your time, luck and resources.
 
I agree--$200 is pretty steep. I would look for one from an early FJ60 and even the flange will match up.

The 3.70 tend to be the least desirable diffs and usually sell in the $100 range. Contact shmukster (Gary Shumach), he parts out a lot of FJ60s and will likely have a diff for you. Very good guy to do business with and good prices as well.

Good luck.
 
Cruiserdrew said:
I agree--$200 is pretty steep. I would look for one from an early FJ60 and even the flange will match up.

The 3.70 tend to be the least desirable diffs and usually sell in the $100 range. Contact shmukster (Gary Shumach), he parts out a lot of FJ60s and will likely have a diff for you. Very good guy to do business with and good prices as well.

Good luck.
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X2 reguarding Gary. Shipping from PA to MO was only $ 35.00 for both .Theres also some 3.70's in the for sale section here on Mud. Good luck, Al
 
KY Longhunter said:
Got a line on an 86 FJ60 3:70 Diff. Will this bolt right up to my 1981 FJ40?
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No, the flange pattern will be wrong, but you can just swap pinion flanges, though you'll have to be extremely careful about pre-load on the pinion bearing.

Or, you can redrill the flange for your driveshaft pattern.
 
Cruiserdrew said:
No, the flange pattern will be wrong, but you can just swap pinion flanges, though you'll have to be extremely careful about pre-load on the pinion bearing.

Or, you can redrill the flange for your driveshaft pattern.
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x2 on drilling. The newer diff flange is a big round thing with all kinds of room to drill in a new pattern (or two). No need to take it off and re-set pre-load.
 
84FJ60 Third Member to 81FJ40 Drive Shaft

Ive found a Thrid Member from a 1984 FJ60.

I was concerned about the flange fitting.

Seller says...Looks like the flange fitment will be fine as the diff is from an early 84 FJ60. Check Kurt's site below:

Cruiser Outfitters
 
Get the front driveshaft too while you're at it if it is available. $75-100 is what I have found to be ave $$ assuming all is good. It has the double cardan (or CV as some call it) joint.
 
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