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4x4 with ignition off?

WarWagon

WarWagon

Well it hits on 7 of 8...
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Does at least one front wheel stay 'locked' in manual shift 4x4 with a thermal actuator and ignition off?

I just don't get enough traction in my driveway with the parking brake backed in. Seriously my truck does a burn out with the engine OFF!

So if I shift to 4x4 will a front wheel hold through the drive line off the parking brake? Assuming the thermal actuator cools off and lets go.

No seriously I am not kidding!!!
slide.jpg
 
Wow. That's crazy. What's the grade on that thing?
But if it has pressure on it, won't it keep it locked?

Sent from my SAMSUNG-SM-G890A using Tapatalk
 
Are you sure someone didn't pull it down the drive?
 
Yes. The Cummins already did this a small amount and I figured it was just the weight of the engine out front on it. New tires on patch and this is the first time it has done this. The grade is extreme on the driveway - you have to get a run at it or you spin out in reverse.
 
Managed to have a used "new style actuator" arrive at my place while cleaning up a yard that had a front diff being scrapped.

So the motor needs a 15002405 spacer included in the 88959465 wiring kit?

Any wiring diagrams someone can share?

And how does the thing unlock exactly? Specifically when the ignition is off or you shift out of 4x4? Is the secret to staying locked with the ignition off switched ignition power to unlock the new motor so ignition off and no power to the old TLA wiring doesn't cause it to unlock?
 
I don't know but thought the new style electric (not the thermal) actuator was powered to retract or disengage always with key on run except when the truck is in 4x4. When in 4x4 its switched somehow to engage. I assume a polarity switch or 4 way switch internal so that it engages when the transfer case switch is in 4x4.

I think the diagram is something like this.

http://ww2.justanswer.com/uploads/therock500/2010-07-08_134048_484577_95_to_current.gif

In your case you could run to a switch and leave it toggled off so that it doesn't retract until you want it to. Otherwise when you go to crank power on run wait to start its going to try and disengage. Maybe it won't have the power to disengage with weight on the engagement.

How do you park now such that you have weight on the park pawl and it clunks when you take transmission out of gear or is held with parking brake so you can take it out of park easy?
 
I think the manual cable is probably the most secure method for you or wire appropriately. But wiring it still leaves a bit of question. I am not sure of the mechanical advantage for it want to disengage????

I know when I step on both of my tractors differential lock and am in a hard turn so power is on the differential the lock will stay engaged (whether or not I have my foot on lock) until I straighten and torque equalizes between engine and both tires then it will pop out of engagement. So I wonder how the front truck differential will react????
 
Park nose up, apply parking brake, let truck roll back onto parking brake (making sure it holds) then put it in park. Always release parking brake after truck is out of park. Park pin will hold and come out ok most times if it is used alone. (Not my preferred method!)

"Hot in run" is the answer. The motor upgrade has to have power to release. So ignition off = no power.

This will be for the times I need to back in and unload before I get the banana truck out of the garage.
 
The new style electric NON thermal actuator is a very simple yet proven design. It has to be powered all the time via the brown wire in the adapter harness. When the 4X4 switch sends a ground signal to the shift motor it engages the axle by extending out a spring loaded plunger that works via a screw actuated ram. Once extended the motor keeps the plunger extended until the ground signal is taken away WHILE it is powered so it can retract the plunger via the screw motor. I've seen several people now connect the brown wire to the wire that is hot when 4X4 is commanded, but not when it isn't in 4X4, and it causes the front axle to stay engaged. Seen one guy tear up all kinds of stuff because of it(cranked torsion bars with the driveshaft spinning all the time on an older 88 truck did a number on his front driveshaft from spinning all the time, and constant CV problems from them spinning the diff and shaft all the time). Fixxed the wiring and no more porblems. GM's new actuator RARELY fails, and is a simpel design that engages as solid as a cable. I see no downsides to it.
 
Sigh! Monthly tire pressure check shows part of the problem. No edge wear on the rear tires. Rear PSI is 70. :facepalm: I told the shop 55 front and 50 rear... So less rubber patch on the road for traction with high PSI and unloaded bed.

Anyway the upgrade wire harness arrived. Just have to install it along with finishing the Banana truck project.
 
You think the guy at the shop you told PSI to actually told the grease monkey to set it at that? When I worked at a tire place, the owner told me that if I couldn't see the MFR suggested PSI on the door, to set the tires at max sidewall for liability reasons.
 
Parking nose-up will put more of the truck's (& engine's) weight onto the back tires. Using the e-brake will do more for you than engaging the front axle. This photo album contains everything I learned while converting my front axle:

 
Steve83 said:
Parking nose-up will put more of the truck's (& engine's) weight onto the back tires. Using the e-brake will do more for you than engaging the front axle. This photo album contains everything I learned while converting my front axle:

Click to expand...

Thanks for that!

It's a truck so it needs to be backed in and unloaded from time to time. Locking in 4x4 is so the front wheels with traction will hold parking nose down via the drive line back to the rear parking brake that I always use on this driveway. It wasn't until new tires that this became a problem on this truck. My Dodge Cummins already slipped some in the past. Parking nose up is the best way of course.
 
OK explain it better that doesn't really help. Why would it matter how the wheels are locked if its the tires slipping on the pavement?

Are you saying its the differential allows one wheel to slip a little then the other because its not a rigid spool???? I think Warwagon said he engages the parking brake and that does not seem to hold it. Its not loading the transmission in park and binding such that it clunks and hard to get out of park.

Is one side the parking brake weak? Seems that could skid one tire???
 
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