no 4x4?
smurfmobile
04-14-2007, 01:42 AM
91 4x4 ext cab S-10, floor shift with pretty lights, and driveshaft, axle, tire lights. 4-wheel drive was throughing mud, tires spinning, going fine. CLUNK... no more 4x4, lights are still on, move shifter, lights go on and off, but no front tire spinnage. Been reading for days, seeing similar probs, but not while running, simple answer or am I screwed?? Or where do I start looking?? Thanx in advance.
smurfmobile
04-14-2007, 02:18 AM
check the flux capacitor, lol,(had to answer myself), as I'm very impatient. But had to say the eng, trans., is very responsive, everything, including heater works fine, no problems starting, running, shifting.
MT-2500
04-14-2007, 09:57 AM
Start basic.
Fuses and power feeds and vacuum to front axle.
Does it shift to and from 4W low range?
Front axle locking in.
Here is a link but is for the newer dash shift.
http://www.automotiveforums.com/vbulletin/showthread.php?t=572914
Fuses and power feeds and vacuum to front axle.
Does it shift to and from 4W low range?
Front axle locking in.
Here is a link but is for the newer dash shift.
http://www.automotiveforums.com/vbulletin/showthread.php?t=572914
vtmecheng
04-14-2007, 07:43 PM
Here is the VT guide to checking your 4x4.
1. Under the battery you will find the vacuum actuator for your front differential. This will have a vacuum hose coming from the transfer case and a cable going to the front differential. Feel this and note the rubber plunger where the cable is attached. Start the truck up and put it in 4wd. Now reach down to the actuator, and please be careful to not touch any moving parts because that would hurt, and see if the rubber plunger has pulled back into the actuator. If it does then go to #2. If not then pull the vacuum hose off the actuator and check if vacuum is seen at this hose. If no vacuum then go to #3. If vacuum is seen then push the plunger into the actuator by hand and plug the hole for the vacuum hose with your finger. See if the plunger stays in or comes back out. If it comes out then you need a new actuator, if it stays in then reattach the vacuum hose and go to #2.
2. Jack the truck up so the front passenger side tire is off the ground. Engage the 4wd with the truck running and turn off the truck. Now see if the front tire tire spins. If the actuator is pulling on the cable to the front differential and your truck is in park/gear (auto/manual trany) your front passenger wheel will not spin. If it does and you are sure that your actuator is pulling on the cable then check to see if the front drive shaft spins with the wheel. If it doesn't then either the cable going to the diff is broken or your front diff has problems. If it does then your transfer case has problems.
3. So you don't have vacuum at the hose going to the actuator. On the transfer case there is a vacuum switch screwed into the housing with three vacuum hoses. One hose goes to the engine for manifold vacuum, another goes to the vacuum actuator, and the last to a high point for vacuum pressure venting. Make sure the first two hoses mentioned do not leak. If they are good then you need a new vacuum switch.
I did my best to read through this for mistakes but if there is one I am sorry, that hole human thing. Good luck and feel free to message me with any questions.
1. Under the battery you will find the vacuum actuator for your front differential. This will have a vacuum hose coming from the transfer case and a cable going to the front differential. Feel this and note the rubber plunger where the cable is attached. Start the truck up and put it in 4wd. Now reach down to the actuator, and please be careful to not touch any moving parts because that would hurt, and see if the rubber plunger has pulled back into the actuator. If it does then go to #2. If not then pull the vacuum hose off the actuator and check if vacuum is seen at this hose. If no vacuum then go to #3. If vacuum is seen then push the plunger into the actuator by hand and plug the hole for the vacuum hose with your finger. See if the plunger stays in or comes back out. If it comes out then you need a new actuator, if it stays in then reattach the vacuum hose and go to #2.
2. Jack the truck up so the front passenger side tire is off the ground. Engage the 4wd with the truck running and turn off the truck. Now see if the front tire tire spins. If the actuator is pulling on the cable to the front differential and your truck is in park/gear (auto/manual trany) your front passenger wheel will not spin. If it does and you are sure that your actuator is pulling on the cable then check to see if the front drive shaft spins with the wheel. If it doesn't then either the cable going to the diff is broken or your front diff has problems. If it does then your transfer case has problems.
3. So you don't have vacuum at the hose going to the actuator. On the transfer case there is a vacuum switch screwed into the housing with three vacuum hoses. One hose goes to the engine for manifold vacuum, another goes to the vacuum actuator, and the last to a high point for vacuum pressure venting. Make sure the first two hoses mentioned do not leak. If they are good then you need a new vacuum switch.
I did my best to read through this for mistakes but if there is one I am sorry, that hole human thing. Good luck and feel free to message me with any questions.
smurfmobile
04-16-2007, 01:14 AM
appreciate info I'll check all this out soon, between tornadoes, rain, snow, sleet, and 50 to 100 mile an hour winds and gusts, havent had much of a chance to crawl around on top or under truck. check out (cnjonline) Clovis body shop is where I used to work. Tornadoes suck.
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