New here with 4wd issues

[mudmantim]

Hi all-

I'm new here, 1st post as I just purchased my 1st Dodge. Can anyone help?

Front 4wd doesn't work.

Purchased truck without front driveshaft.
Seller told me previous owner removed it to get better gas mileage.
Seller said he personally tested with driveshaft from his other Dodge and 4wd worked perfectly.

Installed front driveshaft, attached linkage, and no 4wd.

No 4wd indicator light.

While shifting 4wd shifter I know when it's in the correct locations..."n" is actually neutral to test.

Drives better through snow in 4h, and 4l. In 2h and it's really easy to get stuck. So there is obviously a difference.

Wherever 4wd shifter is at, front driveshaft can easily spin by hand...it never locks. Tested with transmission in all gears, I was stuck so it wasn't too dangerous.

I checked both red and black for vacuum (testing on my finger) and didn't feel any vacuum at all. Tested this in park and neutral.

For the life of me I can't find a fuse. Not sure that would be an issue anyway as 4wd does seem to work for the rear.

Had a mechanic turned backyard mechanic look at it. He's never looked at Dodge's before.
He said transfer case is shot.
I haven't seen him to get more info, as he's gone currently and what I did get from him was through his wife.

Does it sound like the transfer case is shot? Or, just maybe another, easier, less costly issue is causing this?

Googled the **** out of this. Basically I find that maybe transfer case needs replaced, but I found different causes for each issue and not one real cause.

By the way, I'm not a mechanic and haven't really worked on vehicles in over 25 years.

Thanks in advance for your help!

By the way:
1997 Dodge Ram 1500 Club Cab 4x4, 360, auto transmission

 

[Neo299]

I just fixed the 4wheel drive on on my 98. On mine the the axle lock vacuum motor went bad. So I replaced the whole thing with a cable actuated axle lock and that fixed it. Now it doesn't rely on the vacuum to work. This is a link to the one that I bought. 4x4 Posi-Lok PSL400 Axle Disconnect https://www.amazon.com/dp/B004TOLDOA/ref=cm_sw_r_cp_api_F1VHAbA1HEXC2


Sent from my iPhone using Tapatalk

 

[mudmantim]

Currently truck is in the shop.

Unfortunately, my transfer case is shot. Mechanic said it is bone dry, and full of so many shavings you can hear them being churned up when manually turning the front driveshaft.

He just called me this morning. Full of good news, said a hack was working on everything else. Would take $1000 minimum to get it safe.

Not sure what to do. Mechanic is very particular in how things need to be, so I'm betting he's just going way extreme.

Maybe transfer case swap, and be happy.
After all, it just needs to last me until spring.

 

[mudmantim]

Thanks for your reply.

 

[Neo299]

Check your local junk yard. They usually have good deals and the parts are in good shape and are usually checked over before they sell them to you.


Sent from my iPhone using Tapatalk

 

[mudmantim]

Thanks, I'll check some out.

 

[Neo299]

Thanks, I'll check some out.

No probemo


Sent from my iPhone using Tapatalk

 

[Yeret]

Our trucks have a vacuum switch on the transfer case which, when you pull the transfer case lever into 4x4, reroutes manifold vacuum into the actuator on the front axle which connects the axle to the transfer case. Said actuator has two vacuum hoses, one black and one red. I believe (been a while since I've tested this) that in 2wd, the black hose pulls a vacuum and does nothing while the red hose has no vacuum at all. When you engage the 4x4, the transfer case switch reroutes the manifold vacuum to the red hose which actuates the...actuator. In 4x4, you will feel a vacuum in the red hose but now the black hose will pull no vacuum. Basically, as long as the respective hoses "switch" vacuum when you go from 2wd to 4wd, that means that the transfer case vacuum switch is functioning properly.

If you engage the 4x4 and you have no vacuum in either hose or if the black hose continues to pull vacuum, it means that either the transfer case switch is faulty (more common) or the shifter to transfer case linkage needs to be adjusted (less common).

If you have no vacuum at all at the actuator hoses in 2wd or 4wd, you should check the lines between the intake manifold and the transfer case switch. The line going from the manifold to the switch is plastic and isn't going to collapse like a hose would but it could still be breached somewhere.

Me, I ended up swapping the entire vacuum system with a mechanical cable-actuated setup courtesy of Posi-Lok. It's not as intuitive as simply pulling a lever (which you still need to do) but once you get the hang of it, you got no worries at all of the front axle "giving up" and disengaging, which the OEM vacuum-actuated systems like to do ESPECIALLY when they start getting old.

 

[mudmantim]

Great explanation, thanks.

Transfer case was dry, only thing in there was a LOT of dry metal shavings. My mechanic said he may be able to rebuild it, but would be faster to just find a good used one. I think I have a lead on one for a descent price too.

After all that, then it will be time to cross our fingers and hope that all the other stuff magically works.

Thanks.
-Tim

Our trucks have a vacuum switch on the transfer case which, when you pull the transfer case lever into 4x4, reroutes manifold vacuum into the actuator on the front axle which connects the axle to the transfer case. Said actuator has two vacuum hoses, one black and one red. I believe (been a while since I've tested this) that in 2wd, the black hose pulls a vacuum and does nothing while the red hose has no vacuum at all. When you engage the 4x4, the transfer case switch reroutes the manifold vacuum to the red hose which actuates the...actuator. In 4x4, you will feel a vacuum in the red hose but now the black hose will pull no vacuum. Basically, as long as the respective hoses "switch" vacuum when you go from 2wd to 4wd, that means that the transfer case vacuum switch is functioning properly.

If you engage the 4x4 and you have no vacuum in either hose or if the black hose continues to pull vacuum, it means that either the transfer case switch is faulty (more common) or the shifter to transfer case linkage needs to be adjusted (less common).

If you have no vacuum at all at the actuator hoses in 2wd or 4wd, you should check the lines between the intake manifold and the transfer case switch. The line going from the manifold to the switch is plastic and isn't going to collapse like a hose would but it could still be breached somewhere.

Me, I ended up swapping the entire vacuum system with a mechanical cable-actuated setup courtesy of Posi-Lok. It's not as intuitive as simply pulling a lever (which you still need to do) but once you get the hang of it, you got no worries at all of the front axle "giving up" and disengaging, which the OEM vacuum-actuated systems like to do ESPECIALLY when they start getting old.

 

[MT Hillbilly]

gotta love used car sales men!! said it worked fine.... Tried it my self....

 

[mudmantim]

My truck is a 1997, replacing the (according to my mechanic, on the transfer case (not the red tag) 231D, 2.72 ratio transfer case.

One that I found, from a 100,000 mile vehicle, either a '96 or '99, seller mentioned both. On red tag it states 231DHD 272 ratio, but on the white tag it says 231D. Image attached of this red tag.View attachment 120643 View attachment 120643

I've googled this and found a few different threads where people show 231D on the white tag and 231DHD on the red tag.
Why do the tags differ?
Do I need to verify on my current transfer cases red tag that it says 231DHD?

Do you think this will be interchangeable with what I have?

 

[mudmantim]

Also, on my build sheet it says: "Shift-on-the-Fly, 231HD Transfer Case"