Last weekend my dad and I competed in an overnight winter road-rally in my Grand Vitara, up in the Laurentian mountains. It was an AWESOME rally!!

it was my second road-rally in the GV and first big overnighter. I've done a few big overnighters before in my old cars. It had snowed that day so the roads were excellent, with nice big 6 foot high snowbanks in places; rough patches that utilized the bump stops at 50km/h (our stuff in the back was airborne a few times for sure), smooth long straights = 5th gear on snow/ice, and twisty-turny-blind cresty stuff that would rival the Swedish or Finnish WRC events. Coolest part of the night must've been passing by a blue Subaru WRX STi that had the big rally lights on the front, he made a wrong turn and was just coming back on route when we blew past. I kept a close eye on my rearviews and for a place to pull over because I knew he'd be pushing hard trying to make up for lost time, but suprizingly the gap between us seemed to steadily WIDEN for the first while, until we got to the twisty blind cresty stuff and he caught up and passed me. But it was neat that I was able to hold off a big 300hp Subaru for a while.
The 4WD worked flawlessly the entire event and also never skipped a beat before. In fact I never ever hear the "clunk" everyone talks about. There's only two instances that I heard it: 1. When I first got the GV and first good snowfall I went out to an empty parking lot and tried to do some 4WD donuts. It made a couple clunks so I stopped. 2. One time or another I engaged 4WD while at a dead stop and then at "launch" (light turned green) it clunked as the axles engaged. 99% of the time I make sure to put it in 4WD while I'm still rolling, or roll forward slightly to allow positive engagement, at which point the 4WD light would flash once and it would be good from then on.
So like I said, no problems with the GV on the road rally. We placed 3rd in Novice class!! (Novice because it was only my dad's 3rd rally as a navigator).
So, we drive home, all is well. Monday comes and I'm back to work, and after work I put the GV up on the hoist to check the suspension and linkages. All is well.
On wednesday, Ottawa gets hit with a goodsized snowstorm. Well that doesn't faze me one bit, I have my 4WD, REAL snow tires (not just bald A/Ts like every other suv owner has), and the aftermarket4x4 front skid. On the way home from work, some idiot left all his snow from his driveway all over the right hand lane of Riverside Drive. There was someone beside me so I couldn't change lanes so I had to "blast" right through it. Foomph! Bah. Nothing to it, compared to the rally four nights ago.
Except that four nights ago, my 4WD light wasn't flashing, and now it is. Now I know what you're thinking: Hose popped off. That's what I thought too. So thursday, after work, I put my GV up in the air, and pulled off the skid plate.
The hoses are all good. I pulled the hose off the bottom of the differential and hooked the hose up an air pressure gauge, and it goes right up to 7psi and holds solid. Releases the pressure when taken out of 4WD too. This tells me that the air pump and all the air lines right up to the diff are holding just fine, no leaks.
I hooked the line back up to the differential. When placed in 4WD, the airpump in the front seems to cycle once per second. So, I teed my pressure gauge into the system and it pressurizes up to about 6.5psi and then the needle drops to about 6psi, motor runs, brings it back up to 6.5psi, drops, motor runs, air drops, motor runs etc. The motor runs about once per second. So it seems to be leaking down inside the differential.
I was so hoping for it to be the airpump or a hose.
Did I miss anything in my diagnostics? Or any other tricks to try?
Something interesting to mention is I still have 4WD while the light is flashing. Today, it seems the light flashes and I have 4WD for about a minute or so, until the pump seems to "give up", and I have no light and no 4wd - even thought the transfer lever is in 4H.
So, now, what are my options?
Just fix it. Whatever that entails, I called the dealer and a front 3rd member with the air mechanism is about $700ish cost.
Do the SOTF-delete conversion.
http://www.zukiworld.com/month_030104/feature_tsb_shiftontheflyremoval.htm On a whim, while I was at work I phoned a junkyard and priced out a front diff from a samurai. $150. Nice. But then I read the SOTF-delete article. Yeesh. That seems like an awful lot of work just to get rid of the air-SOTF. I've no intention of changing my gearing, or running bigger tires or doing a lift, or whatever. As you can probably guess I'm not that big into off roading (I have yet to actually go out on a mentionable trail), my big thing is road-rallying, which is why I still have stock ride height, stock tire size, and even the swaybar. Can't I just:
Pull my front diff out as it is now, and "permanently engage it", and get manual hubs. After sleeping on it and thinking about it during the day, that really seems like the quickest, most cost effective option. Has anyone out there done this?
My GV is a 1999, with a 5-speed, so it has the steel carrier (confirmed with a magnet today). While it is apart I can toss a seal into the passenger side of the diff since it is slowly seeping. There's still lots of gear oil in it, I changed all the driveline fluids back in late May and I filled the front diff with the front end jacked up at about a 30deg angle to get 1.25L in. When I checked the fluid level yesterday it was still above the fill hole (vehicle level).
So, that's all I can think of right now, any other ideas to consider?
Thanks for any input. It couldn't wait until the fun snow season was over, could it. I wanted to go play in the big snowstorm this weekend too.
James