73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => 4 Wheel Drives => Topic started by: k10caddy on August 19, 2004, 03:48:00 am

Title: Fluid filled th400->np208 Adapter?
Post by: k10caddy on August 19, 2004, 03:48:00 am
I've noticed a substantial amount of fluid leaking from the adapter that goes from the th400 to the np208 on my truck...
has anybody else had this problem?
:(  now am I wrong but I thought that it was a dry connection with no fluid interchange between the tranny and transfercase?

I know the transmission has plenty of atf but I also know that t-case uses atf instead of gearlube.  if the t-case is leaking then can I replace the input seal once I separate it from the adapter or do I need to take whole friggin thing apart to change the seal?  

Title: Re: Fluid filled th400->np208 Adapter?
Post by: CrazyLouie on October 10, 2004, 10:44:00 pm
You have 1 of 2 things happening.
1. The trans output/adapter input seal is leaking
                       OR
2. The t-case input is leaking due to a plugged vent.

In #2, the tcase doesn't create any pressure in the lube system. However, if the vent is plugged, then as operating temp rises in the case, then it will push fluid out the front & sometimes rear output seals. If it is #1, the trans will continue to push pressurized lube circuit fluid out and actually start to fill the t-case. Generally, if you pull yer t-case fill plug(the top plug). If its overfull, it's #1.
If it's low, then its #2. Just my 2 cents worth. Lou~