4wd issues

[jjaawilco45]

how far should the 4wd actuator extend, I've got a problem with my system. i've checked all of the fuses, i don't have a vacumn system. the system seems to select different modes of 2 or 4wd. but when in 4wd (high, low, or auto) there seems to be a serious binding issue in the front end( especially bad when in reverse) I have followed some of the advice that i've seen here, but haven't found anyone that appears to have an issue similar to mine, i've removed the 4wd actuator, started the vehicle, and selected different modes on the dash switch. the actuator extends and retracts fine,( i think) i've measured it to be about 7/8 of an inch. is that a go or no go

thanks, jeff

 

[lesterl]

diffs geared the same? Tires the same?

 

[jjaawilco45]

Yes to both. This is a factory stock 99 tahoe, it's had no performance upgrades. This problem has just recently developed. It seems to drive OK in 2nd both forward and reverse

 

[lesterl]

Are you using 4 low or 4 hi?

 

[jjaawilco45]

This happens in both 4hi and 4lo, it also happens in 4wd auto mode. In 2hi everything seems to work fine

 

[lesterl]

Does it bind in a straight line or only when turning?

 

[jjaawilco45]

Does it bind in a straight line or only when turning?

sorry been away for a while. it only binds while turning. UPDATE: I just replace the 4wd selector switch based on some cosmetetic ussues with the old on and the fact that i've read several things on here that lead me to believe that the switch could be the cause of several problems..... The new switch didn't seem to help very much. I believe that it may have helped in a small way for the auto-4wd mode. this mode seems to be a bit better, but hard to know for sure. regular 4hi and 4lo are still very much a problem, especially when in reverse. there is no vacuum actuation of this system that i can find so i believe that it is either electrical or that i just haven't found that part that's causing me the trouble.

So i'm still looking for advice from someone that has had a similar problem. or i'll just have to take it to a shop to let them look at it

thanks everyone

 

[glange72]

I have a 99 tahoe. Almost all vehicles I have driven with 4 wheel drive bind up if used on dry non slippery surfaces I believe this is normal

 

[lesterl]

pretty much what glange72 said, if it dont bind up in 4x4 straight and only when turning that is normal, now if it is in 2wd and binding up when turning you have the front end still engaged and probably need a front axle actuator.

 

[jjaawilco45]

i understand what you're saying. although i haven't used 4lo very often i have used it, and i recognize the typical binding when in 4lo on dry pavement. however i have used 4hi quite often, as well as auto 4wd, and have never experienced this type of binding on this vehicle. at this point i will be taking it to a shop to have more experienced eyes look at it. i do have a mechanical background, just not any experience working on 4wd systems. i've owned this vehicle for more that 10 years. It's just not acting right.