4WD Actuator

[mjtr21]

Does anyone know where I can buy the Vacuum Actuator for 4 Wheel Drive besides the car dealer. I went there yesterday and they wanted $97.26. I know I can probably find it somewhere else for a lower price. It would be also best if I didn't have to buy on the internet. Thanks in advance.

[ZL1power69]

try a local junk yard.

[laxman21]

Originally Posted by ZL1power69

try a local junk yard.

Got one there for $10.

[MT-2500]

Originally Posted by mjtr21

Does anyone know where I can buy the Vacuum Actuator for 4 Wheel Drive besides the car dealer. I went there yesterday and they wanted $97.26. I know I can probably find it somewhere else for a lower price. It would be also best if I didn't have to buy on the internet. Thanks in advance.

Dealer would only hurt one time.
But if you want to shop around as said bone yard or give your local parts places a call.
Some may have a after market setup on them.
Check this link.
http://www.automotiveforums.com/vbul...d.php?t=665179
Good luck and let us know how it goes.

[herkyhawki]

Please read other threads first. http://www.automotiveforums.com/vbul...d.php?t=665179

Don't waste your time getting one from a junkyard, they just don't last that long.

[Jeremy Fitch]

http://cgi.ebay.com/ebaymotors/Dorma...0161QQtcZphoto

[mjtr21]

Well I found an actuator at Napa for 52.00. I took out old one and replaced it with new one but still no 4WD. I can hear encoder motor working, TCCM under dash still clicks, switch on dash still works. the new actuator works because i started truck and put in 4WD and i reached under battery and i could feel that rubber part which was sucked in as far as it will go. (almost touched the coolant fan doing this haha) So i dont know what else to check for. When i put it in 4WD i can hear a wierd rubbing noise on the right front wheel too almost like it wants to engage. Maybe the shift cable to the front diff needs to be lubed. i will try that tomorrow but i dont know what else to check.

[mjtr21]

i will try to check cable to front differential tomorrow but if its not that then i guess i will replace vacuum lines. on my truck there are three goin into vacuum switch. one goes to actuator under battery, one goes up to vacuum ball on hood and i dont know where thirs one goes. also where would i get these lines and how much? thanks.

[blazes9395]

If your cable is getting pulled by the actuator when you press the 4x4 button inside the truck, then your getting vacuum to the actuaotor. Its not a vacuum problem. Your problem will then lie in the front, either the front differential itself, or the actuator, or related hardware.

[mjtr21]

yeah i will check the differential cable in a little while because when i put it in 4WD i can hear a wierd rubbing/grinding noise almost like it wants to engage the front wheels. so i guess that cable isnt pulling enough. i really hope theres not something wrong with the front axle or something. thanks for the suggestion.

[muddog321]

Looked at profile and 97 Jimmy so np233 case (3 button dash) so I would say look at the vac lines drivers side under hood then down to the 3 port switch on the transfer case. They are most common problem and a partial vac will cause that actuator to only partially pull/engage the front axle coupler.

[mjtr21]

is that actuator diaphragm supposed to suck in all the way or it there supposed to be a little bit not sucked in? cause i bent my arm under the battery tray and i felt while truck was running and in $WD and it was suckin in but not completely. thanks for the suggestion. since tehre is 3 ports on the switch, i know one goes to the actuator and another goes up to the vacuum ball mounted on hood, but i dont know where the third one goes. i think i seen it ziptied onto the transmission filler tube. what is it for?

[JaVeRo]

The third line tied to the Dipstick is the vent line. When you take it out of 4wd the vent line allows air in to release the vacuum on the actuator.

James

[JaVeRo]

This is a pic of the part that the cable pulls. It is a clutch fork on a sleeve with splines inside that stays on the differential carrier until the cable pulls, then it mates up to the splines on the inner axle shaft engaging the front.

In the picture I have the clutch fork pulled with a hose clamp on the other side of the mounting plate to hold it in position until I get it bolted on.

If your cable is not pulling far enough due to corrosion, the sleeve may not be engaging the splines on the axle. If it has been run like that very much, the splines may be wore or broke.

James

[blazes9395]

How are the front axles, specifically the CV joints on the axles. Have they been checked for proper operation? Sometimes the axles could break at the joint. If this happens, the front diff will not lock, and you will not have 4x4 operation. They look completely normal by looking at them on the outside, but the only real way to check them is to get the front up on jack stands(or a hoist) and turn both front wheels separately, while very closely watching the axle turn. The axle should turn smoothly, and in one piece, while the other wheel should slowly be trying to turn in the opposite direction.

A way to check the front axle manually is to disconnect the cable to the actuator, pull it and use some locking pliers to keet it pulled(engaged. If it now wroks, then the front diff is fine. If it doesn't, its a diff problem.

Good Luck