Hey guys,

'98 tacoma a/t, 4x4 w/ 105K
Just got our first good snowing here in Colorado. And come to find out my tacoma doesn't want to stay in 4HI. It slips out for no good reason. Yesterday, it stayed in 4HI for 15 miles before it slipped, then slipped out after 2 miles, stayed for another 10 miles. We were on the highway going around 40 mph, but it slipped out a little later in the neighborhood going 20. I can't figure out what makes it come out. There is no pop or shudder, just real smoothly slips out.

I changed the transfer case fluid the other weekend. It didn't seem dirty or goopy. I replaced with Mobil 1 syn 75W-90. Should I try a non-syn gear oil??? I'm a firm believer in synthetics, but I didn't have this problem before the changed fluid.

Also just zirced all my u-joints and both slip joints. They hadn't been done by the PO so I had the hard downshifting at stops.

Any ideas fellas?

oZ