OK, so I've got a 2003 Chevy Tracker, 4 door, 2.0 L, with the 5 speed manual transmission. I believe the gears are 4.30.

So far, I've installed the OME springs/shocks/struts from Rocky Road, along with the 1" spring spacer, so it's about 2" higher in the back, but only 1" taller in from (the drooping in front is probably thanks to ordering only "medium-duty" springs instead of "heavy-duty" springs, plus the monstrous Calmini grill guard which weighs a ton).

Today the Masterkit1 body lift kit (2") arrived, and within a few weeks my new wheels (15x7 steelies with 2" backspacing to finally get rid of those God-forsaken spacers!). Once the body lift is on, and the wheels arrive, I need to make a decision about tires. I posted a thread earlier asking about the difference in running an LT 31x10.5x15 versus the current P235/75x15's. I think I am satisfied that some 31" BFG's will end up on the new wheels.

So here is the question; 2" suspension lift + 2" body lift allows me to run the 31" tires, but I think that gears are next on the list. I understand that if I can find a wrecked pre-'98 Tracker or Sidekick, I should look for the front diff gears, and the entire rear 3rd member. I believe that the gears in those vehiles are 4.88 in the automatic equiped, and 5.12 in the manual equiped. Is this correct?

I have also heard that by installing the entire 3rd member from a pre-'98 Tracker, I will then have choices of lockers (ARB, LockRight or even a calmini LSD) to install. Is this correct?

The vehicle has been pretty good so far, and I am happy, but this step up to 31's (thanks to the body lift) has made me think about gears, and lockers again. Am I on the right path? Please advise.

I understand that if I can find a wrecked pre-'98 Tracker or Sidekick, I should look for the front diff gears, and the entire rear 3rd member. I believe that the gears in those vehiles are 4.88 in the automatic equiped, and 5.12 in the manual equiped. Is this correct?

NO. 5-speeds= 5.12, 4-speed auto's=5.12 as well. The only ones that are different are the 3 speed auto's at 4.62. All the 4 door Sidekicks and Trackers had the 4 speed. The easiest way to tell if it is a 3 or 4 speed is look at the shifter handle. The 3 speed is more of a T-handle, the 4 speed is more rounded and has a Sport mode button on the center console.

Also, just grab the entire front axle housing with the 3rd member in it, and the rear 3rd member. For the front, buy a Sidekick Sport passenger side CV axle and everything should come together proper. There is more info in a thread I posted a few months ago. I will try find it later.

I just spent the past three hours reading every post I could find about front and rear exles from 96-98 sidekicks / trackers. I read about keeping the existing steel diff housing on my tracker, and just swapping in the third member, lowering the gears to 5.12, while keeping the same 26 spline axles. I think I even read you postings about eliminiting the shoft-on-the-fly function. I think thats where your idea of using the suzuki sidekick sport front passenger side CV fits in.

At this point, I don't know how much I rally understood. In a nutshell, find the 96-96, take the front axles, and replace existing gears with newfound gears. This solves the problem of running 31" tires. Correct?

Does this now mean that I can order the ARB or LockRite or Calmini LSD designed for a sidekick?

You seem to have missed that the only axles which fit without creating a hybrid are from the Sidekick Sport, but if you ARE creating a hybrid, you must get the Sidekick parts from a Japan-built 96-98.

Can you post the results of your wheel findings? I am having some trouble getting 15" rims that clear the calipers.

I am still totally confused about why its necessary to create a hybrid axle. If I just want to swap gears, and I have a 98 sidekick with 5.125 front and rear gears, and I remove the entire 3rd member (front and rear) shouldn't everything just drop in to my 2003 Chevy Tracker?

I thought the whole hybrid axle (or Suzuki Sport model, or Japanese made 96-98 1.6 L axle shafts) was about eliminaing the Shift On The Fly. (Longer passenger side axle shaft)

What am I missing here?

I suppose the front diff gear for the Gen2 is not interchangeable with Gen1, because of the air-operated clutch incorporated in it.

I don't know whether you could pull the third members apart and create a hybrid with the Gen1 R&P, but I haven't seen anyone suggest that, so I would expect that the only way to put the R&P from  a Gen1 into a Gen2 is to swap the entire diffs, and for that you need the hybrid axle, or the Sport unit.

Of course it might be possible, and it's just that people were so keen to get rid of the air-operated clutch that they didn't try the other.

It appears to me if you pulled a R&P assembly from a 96-98 Tracker equipped with SOTF there should be no conflict. 
Then if you also wanted to eliminate the SOTF feature, tie off the diaphram in the housing before assembling the R&P, plug the airline, add locking hubs and you should be good to go, according to Ralley-t.  He stated he had success with this.

It appears to me if you pulled a R&P assembly from a 96-98 Tracker equipped with SOTF there should be no conflict. 

Are you sure that's right? - I understand the air-operated clutch was introduced on the Gen2 in 1999.  I don't know specifically about trackers, but it was not in the 96-98 Suzukis.

so I would expect that the only way to put the R&P from  a Gen1 into a Gen2 is to swap the entire diffs, and for that you need the hybrid axle, or the Sport unit.

another option is to use a Sammy 4-pin carrier, and the thickness of the GV Ring is the same as the Sammy.  This allows use of a lunchbox locker...

or use a ARB carrier.

"It appears to me if you pulled a R&P assembly from a 96-98 Tracker equipped with SOTF there should be no conflict. "

"Are you sure that's right? - I understand the air-operated clutch was introduced on the Gen2 in 1999.  I don't know specifically about trackers, but it was not in the 96-98 Suzukis."

No, I am not absolutey sure about this, because I have never tried this swap to date.  That's why I stated it appears the diffs gear swap would work.  Of my four 1st gen trucks I had only one came equipped with "auto hubs" and that was my was my 2-door 96 LSI.    I recall shifting it to Hi range 4WD below about 20MPH and I don't recall any grinding or difficulties.  Same with pulliing it out of 4WD.

Along the same line, I am considering grabbing a front and rear gear set from about a 2002  2-door GV at the local pick-n-pull to see if I can up grade my gear set from the stock 4.63 to 4.80.   I run 235/75/15 radials (about a 29" tire) and I was hoping to get back closer to the stock axle ratio with the larger tires.  Don't know if they will inter change, but that is what I intend to check out.   I also thought about going with later model 5.12 Tracker gears, but I'm not sure I will ever move up to a 31" tire and i don't want to run higher RPMs than needed when cruising down the road.   If the 4.80 gear set works, they will push a 30" tire better than the 4.63s are currently pulling the 29" tire.  the stock 4.63s gear set does fine, for the most part, but when I get off road, I typically have to run the RPMs up to maintain enough power to move.  I'd rather run the engine at lower RPMs to get where I want to go.

Even crazier... I am actually thinking about investing in one of the "SnowBear" snow plows to push snow around my house, a couple neighbor's homes and to keep our church parking lot clean as well.   They actually make one for a Tracker/GV.  So more gear would be appreciated for this reason as well.  They are "fly wieght plows" and aren't intended for commercial use but I think they would be more useful than the sportsman plow (with the rubber scarper).  I think the snow Bear would work fine for my purposes.