4WD not engaging

[Mark Rinker]

Noticed this weekend no 4WD engaging on my 2002. No dash indicator, no wheels locked in. This truck has the floor mounted, 'manual' selector, not the pushbutton style like my 2001.

I can hear the transfer case whine, so am guessing its just a problem with the hub actuator. Checked the fuse, it was fine. How to go about troubleshooting the actuator? Are these complicated and/or expensive?

[rob from bc canada]

This may be a really dumb suggestion, but just in case - is it possible the wire leading from the transfer case to the front end has become cut or disconnected someplace??

That happened to me once on my 6.5, after a service, and I was stuck in 2wd in the bush, fortunatly not so deep I couldn't get under there, and I don't remember exactly what made me think to look for such a thing.

[Mark Rinker]

Well, when the tech took out the drain plug, nothing came out. The dreaded transfer case leak (which went undetected too long) resulted in many hard parts failed or suspect for an easy rebuild.

$1050 for a new remanufactured unit with 2 year warranty...the rash of repairs to the Dmax's continues, but I am willing to invest in the trucks as they have been very trouble free up to recently, and this all seems like normal wear items, considering the miles and heavy towing/snowplowing use they take.

[mhagie]

Mark, Hate to tell you this But Eric at Merchant Automotive has rebuilt t/cases cheaper than that and they have his updated pump kit to stop the dreaded hole in the t/case.
If you keep this truck long enough the new unit will suffer the same fate.
I went through this a while back, luckily I caught the oil on the tailgate and dripping from the rear axle housing and was able to trace it back to the t/case before any damage.
Bad part was Erik hadn't released the kit at that time so now I will have to buy the kit and upgrade mine .

[Mark Rinker]

Can you send Eric's contact information? Next time I'll look into his products.

The unit I purchased was delivered and turned out to be the wrong one - it was mislabled as a NP 261-XHD (manual floor shift) but was the more common pushbutton, electronic shift version instead.

Soooo, my 'box of parts' was delivered to a local outfit for a rebuild. Since it needed all the hard parts replaced, the bill is closer to $1300 and only 1 year warranty. That doesn't include labor for the in/out. Probably north of $1800 before the truck is back on the road, and at least 4 days of no revenue.

[mhagie]

Sure thing,
www.gmdieseltech.com will get you there.
Between him and Kennedy that's where I get all my diesel stuff.
If you call him about a t/case you'll probably cry when you find out how much extra you spent.
He is in Holland Michigan.
Merle

[Mark Rinker]

Yeah, my bank balance is already crying. You may have read that both trucks have received injectors (warranty), injector lines, glow plugs and thermostats recenly. Thought they were winter ready, but the 02 shucked a transfer case and the 01 needs a waterpump. Bad timing for sure.

The original idea was to get the truck in for service, and back on the road in one day. Now it appears that 3 days will be lost. I could have afforded to wait for something cheaper out of state instead of buying across town.

Who was to know.

[Mark Rinker]

Got the truck back today. Total cost: $1500 for a total rebuild and the in/out labor. 12 month warranty.

[rob from bc canada]

Got the truck back today. Total cost: $1500 for a total rebuild and the in/out labor. 12 month warranty.


Ouch!!

Makes you think it would pay to put some kind of low level sensor in the transfer case, doesn't it.

Any idea how long it might have been leaking?

[Mark Rinker]

Long enough that there were no signs of leakage anywhere on the underside of the truck or on the case. I must find time to take a more active role in monitoring problem areas like this - mentioned it to my service tech (non-GM) last summer, but somehow it was missed.

10K service intervals means that the truck was up 5 times since May, and not sure when it happened, but it could have been avoided.

[cowboywildbill]

I think I read that he 06 trucks have a different setup inside on the problem. Anyone know for sure. I guess I dodged the bullet on our 02. I did check it fairly often and it was filled with transynd. But I understand that when the hole wears thru they can go dry pretty quick.