Transfer case input shaft seal (single lip vs. double)

[SvtLdr]

Is there any problem using a double lip seal on the NP231 input shaft? Original seal in the front bearing retainer (National 13672) is single lip. The seal that came in my kit (TTO F4100) is double lip. Also, on the double lip seal, which side is external, metal side or rubber side? Thanks.

 

[SvtLdr]

Any thoughts on this?

 

[Goatman]

The angle of the lip always points towards the fluid. As far as single or double, if the lip diameter is the same, as in they will apply the same pressure on to the shaft as the original, then I wouldn't worry about 1 lip or two. Be sure to lube the lip(s) with something like Vaseline before sliding into position. A very light coating of rtv on the outside of the seal will help it not only prevent a small leak, but go into position easier too.

 

[SvtLdr]

Thanks for the help, I appreciate it.

 

[Goatman]