Tcase leak at the speedo adapter

[AJs72K5]

My 205 tcase is leaking fluid where the speedo adapter connects. It's enough to where I have spots on the driveway. Do I just need to go to my local GM parts counter and get a new adapter? Is that the easiest fix?

I'm not too concerned about having the right gear inside it yet. The speedo is jacked up with the 39s that are on it now. I'll get it calibrated when I get the new 35s on it.

 

[4X4HIGH]

Search for this in Greg72's post. He had this issue several years ago and found the problem.

 

[AJs72K5]

Found Greg's writeup. I didn't search deeply enough before posting here. I'll try the sleeve out over the weekend and update all. Thanks!

 

[Greg72]

Found Greg's writeup. I didn't search deeply enough before posting here. I'll try the sleeve out over the weekend and update all. Thanks!

Here's the magic part:

And here's a link to my photo library photos of the repair (for future "Search" users!)

http://www.norcalbigdawgs.net/Gallery/album49


I've got close to 1000 photos in various gallery folders. A lot of interesting questions can be answered by surfing around there.

 

[AJs72K5]

Is the sleeve for connecting the speedo cable directly to the 205? Mine has the adapter to correct the speedo between the cable and the tcase. I've already ordered the sleeve, but not sure if I need to track down an adapter too.

 

[bp71k5]

One thing you might also check is the fluid level in the x-case. When I did Greg's mod, I found my case had about an extra quart of fluid in it which caused even the new part to leak. The problem was my reat tranny seal was bad and leaking AT fluid into the x-case.

If you take the fill plug off and fluid pours out, you got a problem.

 

[AJs72K5]

One thing you might also check is the fluid level in the x-case. When I did Greg's mod, I found my case had about an extra quart of fluid in it which caused even the new part to leak. The problem was my reat tranny seal was bad and leaking AT fluid into the x-case.

If you take the fill plug off and fluid pours out, you got a problem.

Why does that suddenly make me nervous? The fluid that's been dripping is just amber. No red to it at all. Hopefully that's a good sign...

 

[Greg72]

I have one of those speed adapters on mine also.... you replace the sleeve on the 205 and then re-attach that adapter. There might be some residual fluid inside it that will drip for a while, but it should eventually stop, since it's not getting any more from the 205 case.

I always thought those little adapters were hoky anyway...and wanted to find a better way to correctly calibrate the speedo.

 

[bp71k5]

The fluid that's been dripping is just amber. No red to it at all.

That's a good sign, but it's free to check.

Greg, what did you do to calibrate the speedo without that adaptor? Or did you go with an electric gauge?

 

[Greg72]

That's a good sign, but it's free to check.

Greg, what did you do to calibrate the speedo without that adaptor? Or did you go with an electric gauge?

I still use that adapter also... There should be a way to calibrate the speedo directly if you send it to a reputable gauge shop (like N. Hollywood Speedometer IIRC)

They do some sort of magnetization procedure to calibrate them. Some day, when I'm much further along in my project I will have to research this more....

 

[ecameron87]

My calibration adapter froze up on me so I tried hooking the cable straight to the transfer case. It would not thread. I guess they are different thread sizes? Now I need to find a new calibration box!

By the way, I replaced the sleeve as directed by Greg72 and it no longer leaks there. I do get tranny fluid into my NP205 though. After one long drive on the interstate it starts seeping out the transfer case breather hole!

 

[bp71k5]

I had a shop replace my rear tranny seal and it made a big difference. I think it only cost $150 to replace that seal and all the seals on the x-case.

 

[4X4HIGH]

Let me step in and say this. The speedo gear and adapters are to correct the odometer, the speedo is a magnatised thing like Greg said. There are 1000 cable turns in a measured mile on a GM speedo.

 

[AJs72K5]

One thing you might also check is the fluid level in the x-case. When I did Greg's mod, I found my case had about an extra quart of fluid in it which caused even the new part to leak. The problem was my reat tranny seal was bad and leaking AT fluid into the x-case.

If you take the fill plug off and fluid pours out, you got a problem.

Houston, we have a problem. Opened it up and red tranny fluid poured out. Will put it in this week to get the seal replaced. At least I know what is causing it. Thanks for pointing me in the right direction!

 

[bp71k5]