The Stovebolt Site Forums The Shop Area Engine Shop Leaking Tranny?

Can anyone tell me what this cable is for and why tranny fluid is leaking from it?
Thanks
http://bradandcharlottes.com/68/tranny%20pic.JPG

Looks to be a speedo cable.However if I can't smash a knuckle on it, its hard to say what the red is. Looks like automatic trans fluid or marvele mistery oil. Wish you luck. :confused:

Looks awfully red like the Ollieberry syrup I make every summer. You could taste to see if it might go well on hotcakes

HAHAHHAHA I think I will pass it on tasting it. LOL

Speedometer cable on a GM automatic. Appears to be leaking at the inner seal, which seals around the shaft of the speedometer drive gear.

To repair, jack up the rear of the vehicle, leaving the front wheels on the ground. this will allow most of the fluid to flow to the front of the tranny. Disconnect the cable by unscrewing the retaining nut. Place a drain pan under the tranny and remove the bolt (with the cross in the head) and clamp. The gear housing should then pull out. If it doesn't put the cable back on and use a pair of pliers on the retaining nut to turn the housing without damaging the threads.

You will find two o-rings on the housing, one inside and one outside. Replace them. Also, inspect the speedo gear shaft for a groove worn from contact with the o-ring. You can usually get the parts at an auto parts store, go to a tranny parts store if there is one near.

When you re-assemble, use some ATF on the parts to lubricate them so you don't damage the seals.

Thanks Fred. I will give that a try. By the way once I have it jacked up should I wait about 5 mins for the fluid to move up to the front? Also how much fluid can I expect to come out when I remove this nut? And last question. What are the "official parts store" name of these seals?

Thanks a bunch Fred.

Ok new info. I cant belive I didnt check this before I posted. I checked the tranny fluid and it is about 3 inches past full. So its over filled. Any suggestions about the best way to get the excess fluid out?

Thanks

Update:

Ok I just took out the speedo from the driver side of the tranny to check the seal and man I am glad I had a bucket with me cause that tranny spit up about 2 1/2 quarts of tranny fluid quick fast and in a hurry. The guy at the tranny shop said a little would come out. Well if thats what he calls a little then I sure dont want to sea a lot. Taking the part down the the tranny shop for a new one. ALso just checked the tranny dipstick and its no longer 3 inches past full. Sitting right on full now.

THREE INCHES??? How'd they do that? it is kinda funny though, no? Getting fluid out isn't hard. If you're doing u-joints through the tail shaft. A cooler line? Siphon back up through the filler? Since you're going to be tinkering for awhile, why not do a tranny service though? I'll bet it's never been done. There's a filter under the pan that can be replaced, and you'll need a new gasket. You'll be able to get an idea of the shape of it's guts by seeing what's left in the bottom of the pan too. Just don't panic - there will be lots of crap in there - so long as there's no actual pieces that are big and shiny - that crap is the wear of the linings of the dozen odd clutch pack plates etc, inside. Don't lay on the forearms when you're replacing the pan bolts - no more than spec torque or getting the fluid OUT won't be a problem anymore.

Yep 2 inches and no I am not kiddine I have a bucket under there that caught the overflow so If needed guess what? Back in it goes. I got a funnel Jim I may actually do that but I want to get the engine running. When I came home tonight I saw something leaking and guess what it was gas. So I had to run down to the parts store to find out they have no 5/16 rubber hose then to another store then back to the house to get that fixed. Just took me 30 mins to run around then another 20 to do the fuel line swap. Man those hoses are hard to get on there when new. Just ran outta daylight again.
Thanks again all I greatly appreciate the assistance given.

Some pics of the speedo piece.
http://bradandcharlottes.com/68/speedo%20side%20view.JPG
http://bradandcharlottes.com/68/speedo%20front%20view.JPG

What's the red on the inside of the housing? I assume you also figured out how to get the extra fluid out.

I just fixed this same problem on my TH400. It would start leaking if it sat for 2 or 3 days, and lose about a quart of fluid. I had put in new seals, but it still leaked. So I took the housing and gear to the tranny store, where they found the groove in the shaft. I put on my glasses and could see it, too. Felt like and idiot, but it stopped the leak.

when you put it back together, check the fluid with the vehicle level. Don't overfill it. Then after you start the beast, check the fluid level in neutral after the tranny's warm.

Yep I found out how to get that fluid out. Went to a transmisison place this morning and took the speedo piece with me. I picked up the o ring, inner and outer seal for 5 dollars. And to boot the guy even installed them onto the speedo unit. THen I told him about the amonut of tranny fluid. HAHA needless to say he seemed a bit shocked about the amount of fluid that compartment held. The best part was that they have a tranny there with cutaways on display so you could see all of its guts. Very cool now I got a better understanding about how it works.
When I get home tonight I am doing the no plug compression test and see what I hear. If all is good then I will put the plugs back in and see what happens. Will report back then.

Brad

Well after a couple days and that massive fluid extraction that the tranny did with a new o ring and inner and outer seals I am proud to report that the tranny is no longer leaking. Now to get the engine running.