Newb questions about th400 and torque converter

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Jason Deckard

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The front pump pumps fluid into the converter through the end of the shaft. If the engine was shut off when the transmission was not on level ground then it might have been a little over full. Just get you some dexron and put back in there.

The converter looks like a srock unit with a double bolt pattern.

For those of you who know that your transmission is in good shape, you can put in a quart or 2 of type f transmission fluid and it will give you a little tighter shifts. Type F has a grit feel to it and helps with less friction on clutches for quicker shifts.
 
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Frankenchevy

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I can’t seem to ID the tag on my th400. All I know is it was made in 86. It reads “86 FVA 15362”

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Also, is this the typical way a th400 and np208 are mated?

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HotRodPC

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Frankenchevy said:
I can’t seem to ID the tag on my th400. All I know is it was made in 86. It reads “86 FVA 15362”

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Also, is this the typical way a th400 and np208 are mated?

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Click to expand...
That comes back to a 86 Military CUCV with a 379 aka 6.2 Diesel. Yes that is the correct adapter and how they're mated OEM. If you're truck is a long bed and your rear driveshaft disappears, I didn't steal the bitch.
 
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If that driveshaft is out of it by any chance, I'd sure like some pics of that driveshaft and also with a tape measure next to it. It appears I'm going to have to get a driveshaft made. Here is my OEM Th400/NP208 combo going in the K10 to K20 conversion truck.

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One guy said " a tablespoon or two" and the other guy said "a quarter of a cup".

Are you Betties gonna be swapping recipes later in PM or will we all be let in on your famous casserole I heard so much about at Bridge Club last week?

Omg did you see the new Martha Stewart peel off wallpaper?

It's so cute! :oops:

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That above is an 81 Th400 code FW comes back from as a 350 V8 4x4, probably a K20 since a K30 would have gotten an NP205.

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Frankenchevy

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HotRodPC said:
If that driveshaft is out of it by any chance, I'd sure like some pics of that driveshaft and also with a tape measure next to it. It appears I'm going to have to get a driveshaft made. Here is my OEM Th400/NP208 combo going in the K10 to K20 conversion truck.

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The drive shaft is still in the truck. I can measure it for you tomorrow. How do you measure it?

I also though it was weird that the front drive shaft has two joints on the transfer case side... not that I’ve seen it all... far from it, but I thought the had just one per end like the rear drive shaft.
 
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Also, I didn’t get a picture of it but I can tomorrow:

There are two holes on the passenger side of the transfer case that are about 3/4 of an inch in diameter. One is threaded and one is smooth. They look like they work together. As if the threaded one is to mount something to the side of the transfer case and the smooth one clocks it with a dowel. Anyone know what that is?
 
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Frankenchevy said:
The drive shaft is still in the truck. I can measure it for you tomorrow. How do you measure it?

I also though it was weird that the front drive shaft has two joints on the transfer case side... not that I’ve seen it all... far from it, but I thought the had just one per end like the rear drive shaft.
Click to expand...
Center of the U joint to center of the U joint is usually how people measure them.

So your front driveshaft is a double cardan joint. Those are common in our trucks. It comes in handy and helps with the steeper angle of the front driveshaft. @bucket probably know more about the purpose of those but it's a good thing for sure.
 
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Frankenchevy said:
Also, I didn’t get a picture of it but I can tomorrow:

There are two holes on the passenger side of the transfer case that are about 3/4 of an inch in diameter. One is threaded and one is smooth. They look like they work together. As if the threaded one is to mount something to the side of the transfer case and the smooth one clocks it with a dowel. Anyone know what that is?
Click to expand...
If it's the holes I'm thinking of, both are supposed to be threaded. That's where the strut rod goes from the Tcase to the bellhousing. See that pic I posted of my Th400/NP208 combo above. If you go full size on the pic, the rod should show up. That's what those holes are for. You really should consider finding you one of those rods. It's helps to keep from breaking the bellhousing on the transmission.

Pics posted here and above post #19. http://www.gmsquarebody.com/posts/424066/
 
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