4WD indicator light after locking CAD?

[1987Comanche]

I'm going to lock the RH axle disconnect tomorrow (it's snowing like crazy, seems like the perfect time to do it) and I'd like to keep the 4WD indicator functional if possible. I have a '90 4.0, AX-15, NP231, D30 Disco (obviously). Looking at the diagrams in the FSM it looks like I could simply connect the 4WD vacuum line to the 4WD switch on the transfer case. Correct?????

[Wildman]

Correct, just remove the 2 lines that go to the CAD, Cap them off at the Xcase switch and leave the one line that goes to the 4WD switch (up under the heater fan) and the light in the dash should still function.

[LEAD_NOT_FOLLOW]

If my memory serves me correctly it's the BLUE line that controls the switch/indicator.

[Wildman]

Thanks.......I couldn't remember which color line went to the switch :thumbsup:

[1987Comanche]

I finished this up (along with a new rad) yesterday and the 4WD light works fine although it takes a few minutes to go out. On my truck blue was a vent line, green was 2WD, and I connected white & yellow together (4WD and 4WD indicator switch).

One odd question though: When I pulled the CAD I fully expected to lose some gear oil. What I didn't expect was gray gear oil??? I didn't see any metal in it and water in it would make chocolate milkshake, correct?

[freakjeep93]

it depends how much water. a little bit will turn it gray more will turn it milkshake and alot will turn it milk white :ack:

[Wildman]

It's not uncommon to find water in the front D30 axle, the end seals are not the best, and if you overfill the differential, the gear oil will seep out of the drivers side :roll: (this I learned)

 

It wouldn't hurt at all to change that oil some time soon if you have no idea how long it's been in there.

 

Glad you got the right color vacuum line........I just couldn't remember which one it was :hmm:

 

Yea, I would think it might take a minute for the light to go off, because the vacuum has to bleed out of the switch, now that you have it hooked up direct.

[1987Comanche]

In a way I'm glad water in the D30 is common. My assumption was that the PO wheeled it and soaked the diff and I suppose that's still possible.

The diff cover is sealed with RTV so I'm assuming that it's factory. I was the first person to crack open the D35, even though the PO swapped it from an '87 (honestly who swapps a diff and doesn't even bother to open it up first?). The D30 was nearly 2 quarts low when I got the truck...I'll add dropping the cover and checking everything out to my list.

[Wildman]

If the cover has RTV sealant, then it's been open before, OEM would be a 'paper' gasket.

 

Some people just don't want to spend the $3.25 for a new gasket :roll:

 

The D30 only calls for 2.5 pints of 75W-90 gear oil, That's just a little more than one quart, so.....you could have over filled it by adding 2 quarts :hmm:

[1987Comanche]

It was 2 bottles but one was already open...it may have been closer to 2.5 pints. Either way the thing was empty.

This morning was the first trip on the interstate since locking the front axle. I have a new vibration that is quite pronounced at 60MPH +. Around 65 the turn signal stalk vibrates like crazy and you can feel it both through the wheel and floorpans. I'm thinking front driveshaft U joints? Figure that's the only thing that started moving that was essentially stationary before.

[Pete M]

definitely possible.