With either system, the front driveshaft rotates when the vehicle is in motion. Whether you're in 2WD or 4WD, doesn't matter. This is what allows "shift on the fly". You'll still have that ability using the Bravada axle shaft and tube. You will still be able to do mode shifts and range shifts as usual. You'll probably notice a decrease in fuel mileage, but oh well

The switch on the Blazer axle tube is a simple ON/OFF (spring loaded off) switch that tells the TCCM when the right front axle is engaged. I have not done this modification so I can't say for sure how the TCCM will react to it. I'm curious to know, so please post back with the results. The only problem you might encounter is this: When in 2HI and selecting 4HI, (mode shift) the TCCM might command the encoder motor back to 2HI. If this happens, you'll need to jump the two terminals in the axle engagement switch connector together. As long as it stays in 4HI, range shifts will not be a problem. Be aware, the lights in the 4X4 switch might blink, indicating a trouble code. If this all works out OK, it would be a good idea to disconnect the vacuum connector from the transfer case and plug all 3 vacuum lines. Good luck and keep us posted.

 

I could not get the damn seal out of the axle tube. It was very tight. I could not get any leverage. I did not have access to a vice so I came up with this. I bolted the tube to a piece of 2X10 and screwed the board to the studs in my garage at about 6 ft high. I got plenty leverage then. I tried the seal removal tool but it was way too flimsey and the handle bent all to hell. I found my large curved prybar and commenced to pull down and up and sideways on the inner lip of the seal and sure enough it began to budge until it came out. The I did the same to the bearing. I was careful to not score any surfaces. It worked for me, maybe it will for others. Thanks for listening to me and the advice. I will take more pictures as I progress.

 

I got everything apart and had the usual stubborn nut/bolt but nothing broke off. I will be reassembling it today and test driving for 4X4 function. When I pulled off the axle tube, there was no gear oil in the diff. I filled it and within one hour I noticed a small pool of fluid under the driver side of diff where cv joint goes into diff. So now I have a leak. Does it make sense to assume it is the seal on that side that is bad? What do I look for to determine where leak is? Thanks again for all the help. I have some more pics I will post later.

 

Before you drive it, and sling oil everywhere, you should be able to see where it's coming from, and the axle seal is a good possibility. The half shaft must be removed to replace the seal. Same procedure as the passenger side, except the driver side does not have a tube.

 

I been looking at an exploded diagram and I think the seal is pressed in on the diff?! Is that right? does the whole diff need to come out or can i get to it by prying the CV joint out and exposing it??? Thanks again.

 

After you remove the halfshaft, the seal is exposed and it's replaced just like the passenger side seal. No need to disassemble anything once the halfshaft is removed.

 

thanks again captain hook. I filled the diff until fluid poured out of fill hole and drove for about 1 mile in snow and ice and it drives like it's in 4WD now. I didn't have time to perform any other tests yet to confirm it is in 4WD like jacking right front wheel up and rotataing wheel. The diff may have been dry since I bought it as I never put it in 4WD drive until this year and then I noticed it wasn't working. That's what started all this. How can I tell if diff has been damaged by being dry?. If I haven't tried to engage in 4WD before, would the front diff gears have been moving while in 2WD?. All I ever drove it in was 2WD. Is the seal the same as the one I just installed in the passenger side axle tube? The company sent me two of them. I hope so. Thanks again, I really appreciate and respect your input. I'm getting closer and closer to solving this!!!!

 

I think it uses the same seal on both sides, check with a reputable parts store to be sure.

As for the differential and 4WD, take it to a snow covered parking lot, select 4WD, have someone outside the vehicle watch the front wheels, if one of them spins, and the differential is quiet, you got lucky

 

I tried driving in a snow covered parking lot but could not tell for sure if front tires were spinnin. I saw spin-out marks behind rear tires but not sure about the front. I had my girl look at passenger's side wheel while I gave it moderate gas but she could not tell. We'll try it again tomorrow and I'll have look at both sides. Should both front wheels spin in 4HI, or left or right one or a random one, like the one with less traction? I jacked front right (passenger) wheel off the ground while in 4HI and car idling and in park and right wheel would not rotate. Does this confirm that it is in 4WD? When I pushed button to put it back in 2HI, the wheel still did not spin around. Is this because I now have the AWD axle in? I also haven't heard any noises. Thanks again for everything, This is a great site.

 

It should not rotate when in 4WD, but, it should release when you select 2WD. Make sure the right front brake caliper is free and not applying the brake.