I have a chevrolet auto trans (not sure which one) but where the speedometer cable ties in, it has a single 3/8 bolt holding it on, its on the right side of the transmission, looks like a rubber O-ring sealing it. Can I pull that cable out and replace the O-ring with out dropping the trans pan? or do I have to drop the pan to fix this seal...cannot stop a steady leak of fluid. thanks for any help!
Shouln't need to drop the pan but it may spill a little if it sat a while and the converter is drained.
Usually it's the seal inside that fitting that leaks the most. The gear will get a groove worn in it too. So don't expect it to stop leaking if you just replace the oring on the outside of the speedo gear sleeve.
If you can't finger it out on your own Google is your friend for simple stuff like this. http://www.google.com/search?q=fixi...-us&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1
yeah, I thought that was kind of strange. It could be on the passenger (right) side and be the detent cable on a TH350. Or something else. Changing the speedo gear seal may be pretty easy, if you can find the parts. I had fun trying to find these parts a couple months ago when I was in Amarillo...ended up at a transmission rebuilding shop, they had the parts and no charge for them.
The housing tends to eventually oblong on the 350 and 400s and even if you replace the O ring, you may still have a leak. As a friend said this morning, I've never had a Gm tranny that didn't drip something.
My apologies to my earlier post, it is the detent shaft, not the speedo shaft that is leaking. I am guessing that dropping the pan in necessary to be able to unhook the detent cable in order to replace the O ring? The transmission has a short tail shaft so I am assuming it is a TH350? Can someone tell me how to go about fixing this? appreciate all the help!
The cable could be bad, they get cracked and leak. Or it could be the seal, the early design cables use an O ring, later ones use a much better sleeve type seal. You should be able to replace the cable without dropping the pan. The wire it hooks to will spring up, so you just need to disconnect the top end of the cable, then remove the bolt, pull the cable housing out of the trans an inch or two, and unhook the end of the cable from the wire.
And while your under there replace the seal for the dipstick tube. It's right there near the T/V cable housing. N.N.
And be sure to grab the cable that's sticking out with a vice grips when you pull the detent cable up so it doesn't snap back into the trans or you will be dropping the pan. And as some food for thought, I had a TH 350 thans that was leaking, ( I posted a thread a few months ago ) and it was dripping at the pass side front corner of the pan. I replaced the pan gasket, detent cable gasket, and dip stick tube O rings. Still leaked. I went under it to check again and there was a small amount of trans fluid on what I thought was about a 5/16 bolt in the side of the trans just above the pan between the cooler line bosses and the modulator. When I went to wipe it off it spun in my fingers, turns out it was a plug that had loosened up. (The fluid was dripping onto the vaccum line and running forward to where it turns to go up to the intake and then dripping onto the front corner of the pan.) I have no idea why it's there but when I removed it to put some lock tight on it, it dripped slowly. Put it back in and tightened it down and no more drips. About drove me crazy, I hate it when something leaks. Anyway, it's just a heads up if the other things dont stop the leak.
That 5/16 bolt is a pressure tap,if it came out you would blow all the fluid out in about a minute and a half right on the exhaust, and you can imagine what the result would be.!! Now onto the detent cable leak repair.... Yes the newer ones are plastic and can crack requiring cable replacement, however if not cracked to access the o-ring or boot seal first "unhook" the cable off of the throttle at the carburetor, that will give you the slack to pull the cable off the trans case to access the detent "rod" that connects the cable to the detent linkage inside the pan letting you replace the seal with out pulling the pan. Then pull the cable and you will see the "rod connection, too difficulty to describe in words how it connects but will be obvious visually. You wont need vise grips to hold the rod from falling back in the trans, it is longer than that , however you will need to pull the "rod" back out when reattaching the detent cable, yes it is spring loaded. Have fun,easy to do but usually very tight doen there with cooler lines and exhaust right where you dont want them
If you mistook the kickdown cable for a speedo cable, I suggest you pay someone to fix it. Because if you screw something up it'll cost even more to fix it
You make a good point, but I have to learn somehow,so if I screw up it sure wouldn't be the first time. Appreciate all the help and comments.
Yes education cost money!! Go for it ,take your time!! I like your attitude in trying to fix it your self!! We all started somewhere and had to learn!! Good luck Pete
you have the internets, so that puts you a step or two ahead of where many of were when we had to figure this stuff out on our own.
Pull it out and replace the O-ring if it is a later 350 it will have a boot instead of o-ring.If it is an o-ring be sure to use a small amount of silicone on the seal. If it is the boot style the install the boot in the trans case and then intall the cable into the boot.
If you don't know what trans you have take it to a shop and get a estimate then you will know what type trans and what parts they think it will take. Then get the parts and give it hell.
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