need help w/ 4wd please read

hey guys i posted this once before but i didnt get any feed back i would really appreciate it if anyone could point me in the right direction any comments would be helpfull thanks...

Ok so I own a 88 chevy k1500 and the 4wd dosent work properly. i have been having a hard time diagnosing the problem so i am hoping some1 will be able to help me out.

When shift lever is in the 4wd position, in either 4 hi or low, it doesen't always engage, or when shift lever is in 2wd the 4wd will engage and the front drive shaft will spin without being locked into 4wd

I have tested the actuator in the front differential, replaced the switch on the T-case and checked for power at the connections. I dont know were to go with it next any ideas on what it could be?

there is a vacum deal under the battery that when you pull the lever in to 4 that moves the pin that locks and unlocks the front diff. if it is unhooked the 4 wd will not work

Now are you saying that the actuator in the front diff. will enguage by itself, or it stays enguaged after shifting out of 4wd.

the first thing to do is ajust shifter into 2 wheel drive have someone hold it in place while you ajust it from the bottom next question does it have locking hub or automatic. is the actuator cable or power let me know

Now are you saying that the actuator in the front diff. will enguage by itself, or it stays enguaged after shifting out of 4wd.

yea the actuator enguages its self when i am in 2wd but it dosent always do it its really random

i was told that it could be a short and im sure that is possible too, but i always thought that if it had a short it wouldnt get power?

How many pins does the 4wd acuator have? If it is a two pin that I would upgrade to the 3 pin (Dealer only), or get a cable pull acuator. Yes it could be a short, check the connector at the t-case to see if it is melted together, that it what tells the truck to lock in the front diff.

A lot of people use the word short to describe any electrical malfunction because they just do not know any better. The term short is used to describe an undesired path to ground in an electrical system. What you are thinking of is an open, an open in a circuit will keep you from getting any power to actuator. If you want to troubleshoot this problem see if the electrical connector is getting any voltage when it is malfunctioning. Another thing you could do is disconnect the elsctrical connector when it is supposed to be in 2wd and the front axle is locking up, if the front axle is locked with the electrical connector unplugged it is the actuator, if it is not you are looking at the switch

How many pins does the 4wd acuator have? If it is a two pin that I would upgrade to the 3 pin (Dealer only), or get a cable pull acuator. Yes it could be a short, check the connector at the t-case to see if it is melted together, that it what tells the truck to lock in the front diff.

cable pull actuator huh? that could work for me how much do they go for? is it east to hook up? i think that would solve my problem for good

your actuator is only supposed to have voltage in 4wheel high & 4 wheel low
only. sounds like adjustment problems or get a hold of a wiring diagram somewhere . some shops with mitchell on demand will print you a copy for a
small fee. they also can print you out a copy for dianoises & repair on 4x4s.

I found the cable actuator on www.4wheelparts.com I think that they are about $150. Have not got one my self yet, but am going to. Tired of the acuator enguaging slow. Read the instructions, it looks very simple to install.