2nd Gen Non-Engine/Transmission 4x4 Posi-Lok for CAD frontend

[SheldonBates]

Has anyone had experience with the 4x4 Posi-Lok (Part No. 400 for 1994-2002 Ram 2500, 3500) manual front axle engagement kit? I have a '96 2500, 5 speed manual shift with 204,000 miles that I just purchased. So far the stock CAD system seems to engage the front axle OK but I am old school (simple leaf sprung front ends with manual locking hubs) and prefer to manually engage (lock in) the front end when preparing to use four wheel drive. From the info on the Posi-Lok web site it appears to be well designed/engineered and reasonably priced. I wasn't able to find any info in the TDR back issue archives. but I may have missed something. I am a new member to TDR. Thanks for any comments or thoughts on this.

 

[LHastings]

That Part No. 400 is a cable kit that replaces the vacuum actuator cad. When you pull the cable it locks your axles together but you will have to still engage the transfer case to put into four wheel drive. I have not tried it yet, it looks like a good kits from the pictures.

 

[DWeaver]

I used a cheaper knock-off one than the Posi-lock for my '96 and I like the manual engagement of the front axle. I can use 4 lo to back up the trailer and still have the turning radius of 2 wheel drive.

I put my kit in to eliminate the vacuum lines.

The drawback is the pull knob now taking up space in the cab, and the cable going thru the firewall.

 

[rMetzger]

My truck has it. I installed it myself. I'm a fat pharmacist who used to have LOTS of wrenches, hammers, etc. etc. and it took me about an hour or two. Somebody competent could probably do it in 30-45 minutes. Be careful not to destroy the gasket that seals the axle to the new actuator enclosure. If you do, it's easy enough to make a new one from cardboard. Torqued down nicely, and then given time to absorb some of the gear-lube it won't leak. (Yes, I'm a redneck). You can feel the collar engage, and, in case you're still worried, the contact switch that turns on your dashboard "FWD" light stays in place. and will light up just like before.

I like it a lot.

These two details might be construed as "drawbacks", but, only by someone really, really picky, who's never dealt with farm equipment. (keep in mind that a proper truck is really a nicely appointed, street-legal tractor, when you get right down to it)

1: you need to slow down to about 1-2mph to pull the knob and engage the collar. Otherwise, you get a chatter like a newbie learning a manual transmission.

2: you might need to reverse and turn your steering wheel a little to disengage (de-torque) the collar, while pushing the knob back into its disengaged position.

These little trade-offs of convenience pale in comparison to the mess you might get into without your front axle working.




Oh, yeah. Remove the vacuum lines that lead backwards to the top of the T-case, and cork off their formerly-important ports. They just leak, anyway, and if you ever observe that no matter where you put the HVAC knob, all you get is defrost, it's because you've lost vacuum somewhere. The flapper-thing inside the dashboard is vacuum-actuated, and anything that costs you vacuum will put your damn flapper-thing into its default position, which is "defogger". Took me a while to track that down, while refrigerating my windshield in a highly humid environment.

 

[SheldonBates]

Thank you one-and-all for your comments/opinions. Sounds like a good way to go. I do plan on purchasing one of the PN 400 kits and will install it soon. Removing the vacuum lines and vacuum motor and the availability of 4L in two wheel drive as you mentioned DWeaver, are definitely goals of the installation. Also, being able to "feel the collar engage" as you mentioned rMetzger is the principal reason I want to make the change. I will also remember your point about how low vacuum affects the proper operation of the defrost mode of the HVAC unit, good to know. And yes, I heartily agree, a proper truck is (should be!?) basically a "street legal tractor. " For example the early civilian 1945 WDX thru the 1960's WM300 series Dodge Power Wagons. Grand old machines.

 

[Bob V]

My truck has it. I installed it myself. I'm a fat pharmacist who used to have LOTS of wrenches, hammers, etc. etc. and it took me about an hour or two. Somebody competent could probably do it in 30-45 minutes. Be careful not to destroy the gasket that seals the axle to the new actuator enclosure. If you do, it's easy enough to make a new one from cardboard. Torqued down nicely, and then given time to absorb some of the gear-lube it won't leak. (Yes, I'm a redneck). You can feel the collar engage, and, in case you're still worried, the contact switch that turns on your dashboard "FWD" light stays in place. and will light up just like before.

I like it a lot.

These two details might be construed as "drawbacks", but, only by someone really, really picky, who's never dealt with farm equipment. (keep in mind that a proper truck is really a nicely appointed, street-legal tractor, when you get right down to it)

1: you need to slow down to about 1-2mph to pull the knob and engage the collar. Otherwise, you get a chatter like a newbie learning a manual transmission.

2: you might need to reverse and turn your steering wheel a little to disengage (de-torque) the collar, while pushing the knob back into its disengaged position.

These little trade-offs of convenience pale in comparison to the mess you might get into without your front axle working.




Oh, yeah. Remove the vacuum lines that lead backwards to the top of the T-case, and cork off their formerly-important ports. They just leak, anyway, and if you ever observe that no matter where you put the HVAC knob, all you get is defrost, it's because you've lost vacuum somewhere. The flapper-thing inside the dashboard is vacuum-actuated, and anything that costs you vacuum will put your damn flapper-thing into its default position, which is "defogger". Took me a while to track that down, while refrigerating my windshield in a highly humid environment.

If you shift the transfer case into 4WD first you wont have any grinding.

 

[rMetzger]

If you shift the transfer case into 4WD first you wont have any grinding.

I usually "do" the front axle while still on pavement, and engage the t-case when I get to the bad surface. (around here, that means "beach sand")

 

[Cosmo]

I put one on my 86 w250, one of the best reliability upgrades.

 

[AEdelheit]

You can also do a CAD delete and make it like the 3rs gens where it's constantly engaged. I know a few people that have done it and been very happy.

 

[Bob4x4]

You can also do a CAD delete and make it like the 3rs gens where it's constantly engaged. I know a few people that have done it and been very happy.

With a one piece axle shaft

The factory Cad system is very reliable as is. if you live in the snow belt of course corrosion of the tubes will be an issue,but so will a pto cable
My 94 system still works great and has never had any repair. The transfercase has been in and out a number of times for clutch experiments and as long as the plumbing is treated with respect it will hold up well.

 

[rMetzger]

With a one piece axle shaft



The factory Cad system is very reliable as is. if you live in the snow belt of course corrosion of the tubes will be an issue,but so will a pto cable

My 94 system still works great and has never had any repair. The transfercase has been in and out a number of times for clutch experiments and as long as the plumbing is treated with respect it will hold up well.

There are also some who have done the $3 fix. Open the CAD housing. Slide the collar over to the "engaged" position, and then tighten on a regular old hose clamp behind it. Make sure the thing can rotate without rubbing inside the housing and close it back up again. Others, who didn't want to do that, just tack-welded it in place and closed it up. Voila! Axle always ready!

 

[JMcCoy]

I have the posi-loc and like it. It is bandaid for a bad design though. The posi-loc does not address the weekness of the CAD axles. Only the CAD delete axle will do that. The posi-loc is 100 times better than the unreliable vacuum actuator.



You do not have to go slow or reverse to engage the posi-loc. You just shift the transfer case in first. When shifting back to 2wd, also shift the transfer case first and then the posi-loc. Hold the posi-loc with pressure and be patient. It will engage and disengage in a few seconds. .

 

[AEdelheit]

There are also some who have done the $3 fix. Open the CAD housing. Slide the collar over to the "engaged" position, and then tighten on a regular old hose clamp behind it. Make sure the thing can rotate without rubbing inside the housing and close it back up again. Others, who didn't want to do that, just tack-welded it in place and closed it up. Voila! Axle always ready!

That doesn't do anything if the CAD has Allread chewed up the axles which I have seen a lot of.