76 4 speed rebuild or not? (1 Viewer)

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Hi all, I purchased a 76 fj40 with a 350 that was smoking so I pulled the engine and I'm trying to decide if I should go through the 4-speed trans and transfer case also. I don't know anything about them, other than my 50-mile drive home didn't provide any indication of any problems.
The fj40 came with a 350 attached to a Downey bell housing and 4speed trans. The transfer case has a Fairey overdrive if that helps.

Since this is my first FJ40 project, what are some recommendations, and why? Rebuild or Leave it alone?

Thanks!

Dano
 
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I say run it.

If it ain’t broke, don’t fix it.

I think you will find the OD Unit hard to get parts for.

Run it until you are sure there’ something broke.

One things these setups do is pump oil from the TC to the transmission when the internal seals fail. You find this when you pull the tranny plug on the side, and oil gushes out, or when it starts coming out of the shifter on the top.

There is a bypass hose solution that runs between the fill plugs that’s a “band-aid” solution, but I’d gust recommend checking them regularly.

Have fun with the truck.

Rocky
 

65swb45

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If the motor is out, then the trans is out. Personally, I could not NOT look if I had the opportunity. More so if the truck was new to me and had any engine other than original under the hood.

Pull the side PTO cover and check for spline wear on the transmission tail shaft by wiggling the input gear. Pull the t-case top cover and Check spline wear on the hi-lo shift collar by holding the hi-speed gear while rotating the parking brake drum.

If parts are needed, I have a shop:

www.marksoffroad.net
 

Lil'John

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Unless it has an issue or is leaking, the only thing I would do is replace the seal between transmission and transfercase. Otherwise, run it ;)
 

reddingcruiser

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I agree with comments recommending you open up the transmission and t-case, and evaluate their condition. Assuming all is good, this will also be the best (and easiest) time to replace gaskets and seals.
 
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I pulled the cover off the trans and it looks new, no grinding marks so that's good.
I tried to pull the bottom of the Fairey overdrive box apart because it's starting to drip and the last owner used a gray silicone to seal it to the main case.

Does anyone have a suggestion to split the case without breaking anything? I already broke a putty knife, so it has a good seal.
 

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