4wd system operation 98up Blazers

[Barnes888]

Hey guys, i've read over this article and i think i know whats going on here. But i seem to have a bit of a different problem on my 2003 GMC Sonoma 4x4 non-Zr2. My truck 4x4 lights all work, and i can go from 2HI to 4HI no problem. As well into 4LO. The problem comes when i go to shift from 4HI to 2HI while driving. The light will change on the dash, but then it doesn't seem to want to disengage out of 4HI straight away and after a bit of time, the front end will suddenly pop/clunk and it will then be in 2HI. I havent had time to pull the battery out yet and check the vaccum lines nor the actuator. but if anyone could point me in any direction of where to look (saving me abit of time) it would be greatly appriceiated.

Thanks!

[reb78]

I'm having some issues with my '99 Blazer as well....When I push the button for 4hi, low or auto, all it does is blink lights at me. I have replaced the TCCM, encoder motor and actuator. Any other suggestions besides taking it to a dealer. I'm pretty good at DIY so I would like to do as much of the work on my own as possible.

[tim153]

My 98 Jimmy has issues going into and out of 4WD. I have read over the forum but dont see anything like the problem I have. I have 3 buttons ont he dash. When in 2WD and push the 4WD button both lights flash. It stays in 2WD untill I slow way down (under 5 mph) It will go into a neutral and then a loud clunk and it feels like someone hit me in the rear end. I have it in 4WD now but scared to try putting it back into 2WD.

[markdw]

Hi Guys,

Newbie here, I was wondering if anyone knew of a source for the pins on the connector that goes to the TCCM mine is completely corroded. Anyone know a site or a part #?

Thanks,

Mark

[spenser]

YOU GUYS ROCK! Had an Ice storm here in Pennsylvania this morning. Hit the 4 wheel drive button and nothing happened! Read this link found the vaccuum line off the selinoid that is mounted on firewall. Splice a new piece in and HOORAY! 4 wheel drive is back on!

Thanks Much!