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Discussion Starter · #1 ·
New member here.

I have had my truck ('70 CST/10 long fleet) for about a year now. I have been slowly undoing atrocities brought on by the P.O., just about at the point where I'm happy with the truck.

On two occasions over the last month or two I have gone out to the garage to find a puddle of ATF under the truck. Not a few drops, either. In both cases the truck had not been driven for a week or so. This has happened twice with about a month interval. It's a 700R4 trans, no visible leaks at the normal spots: pan gasket, dipstick tube. It looks like the fluid is coming out of the cover between the transmission and the engine.

I'm kind of a newbie when it comes to automatic transmissions (all my other toys are manual), so I don't know what the possible issues may be. Any ideas?

Thanks in advance,

Dennis
 

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Sounds like the oring that seals the front pump has gotten old and brittle.What happens is when it sets a few days fluid drains back from torque converter and the fluid level rises above that point.Front hub seal usually only leaks while running.Verify for sure the pan gasket is not the culprit.A lot of auto parts will sell ATP brand and I find they will leak.I always use GM pan gaskets with no problems at all
 

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Yep sounds like front seal. Not a hard thing to change but the trans does have to come out. If you should happen to have a chrome dip stick tube they leak very often. To stop that I clean the chrome off before installing. You can remove the cover and look up inside to see where it is coming from.
 

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Discussion Starter · #4 ·
Thanks, guys! The pan gasket is tight, and I don't see any evidence of leakage around the dip stick tube (not chrome, just painted).

I wasn't looking forward to dropping the trans, but it looks like it's now on my to-do list.
 

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Discussion Starter · #5 ·
I think I dodged a bullet - it looks like the leak is coming from the speedo cable where it connects to the transmission. Isn't there supposed to be an o-ring in there? I can't find anything. The cable looks a little rough, so I'll take the opportunity to replace it while I'm messing with it.
 

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I think I dodged a bullet - it looks like the leak is coming from the speedo cable where it connects to the transmission. Isn't there supposed to be an o-ring in there? I can't find anything. The cable looks a little rough, so I'll take the opportunity to replace it while I'm messing with it.
Mine was leaking there, I had to replace the speedometer bullet as its called, that is where the o-ring is....
 

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Discussion Starter · #8 ·
Another P.O. atrocity

When I removed the speedometer housing to replace the O-ring, here's what I found:



It seems like rather than replace the O-ring, the P.O. smeared it with RTV and re-installed it. Really? It took longer to clean off all the goop than it did to actually remove and replace the part.

So far, so good - a road test this weekend will tell me if I was successful.
 

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Still straightening out that kind crap on mine from the previous owner.. anim_63
 
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