Transmission speedo thing leaks... replace or repair?

[Skunksmash]

That weird thing that sticks out of the side of my 700R4 in my 87 is leaking. Its not just a speedo sensor, it is said that it also can somehow adjust for different tire sizes. I've found them here and there, they sell them at autozone and orielly's and such.

But I've never replaced one so I thought I'd ask. Do those things usually leak? Or does the leaking indicate some kind of internal problem? Is it just some kind of O-ring in there that usually goes bad? Didn't want to buy a replacement and install it before I had some kind of idea of what's going on.

[Skunksmash]

Oh its called the speedometer compensator. Or speedometer adapter. Sticks out of the trans and the speedo cable plugs into it. Its something like this, although mine doesn't look exactly like it. Can't find one for sale anywhere right now.


http://www.oehq.com/acdelco-parts_15...FWaoPAodB1EAMA

[JRANGER]

Its a speedo gear housing and its cheap...I think like $10 from jegs

I had the same problem and replacing it solved it

[clinebarger]

Just "Reseal" the speedo housing. You need a outer O-ring & Driven gear seal.
You have a "Ratio Adaptor", Used to correct speedo's when running over sized tires...Pic.

[clinebarger]

Forgot the pics....

[Skunksmash]

It is in fact a speedo compensator for the oversized tires. Here is a pic of mine. You can barely see the speedo cable off to the side, kinda up there in the top left of the pic. It kinda flows down and screws into the top of the thing that's leaking. That's an old pic, I already replaced the tailshaft seal.

[JRANGER]

whoops my bad...Wrong tansmission sorry

[Skunksmash]

Anybody know where to buy one? I can't seem to find one for my truck anywhere right now. Oreillys, Autozone, Rockauto, nobody has any. They got other ones but not mine.

[hatzie]

Originally Posted by clinebarger

Just "Reseal" the speedo housing. You need a outer O-ring & Driven gear seal.
You have a "Ratio Adaptor", Used to correct speedo's when running over sized tires...Pic.

X2 on this. It's leaking through the transmission speedo gear housing into the ratio box. Once you replace the leaky seals it'll stop.

The part in your picture is a ratio adapter box. There's no fluid or seals inside the ratio box. It's attached to the piece you need to re-seal.

[hatzie]

[Skunksmash]

Ok cool thanks. I don't have much experience with that though. Is that something I just walk up to the counter and tell them "I need a new gear seal for my speedo adapter"? or is it something I need to order somewhere? Can't find anything on it anywhere right now which is weird cause I found them all day long about a year ago when I just thought it was the tailshaft seal. Needless to say I don't drive the truck a whole lot. For now.

[Skunksmash]

Originally Posted by clinebarger

Just "Reseal" the speedo housing. You need a outer O-ring & Driven gear seal.
You have a "Ratio Adaptor", Used to correct speedo's when running over sized tires...Pic.

Is the O-ring actually responsible for holding back any of the fluid? The guy I ordered from told me I just needed the thick orange seal.

[clinebarger]

Originally Posted by Skunksmash

Is the O-ring actually responsible for holding back any of the fluid? The guy I ordered from told me I just needed the thick orange seal.

The Outer O-ring isnt leaking, But I always change it along with inner seal.