What to watch out for: '12 Crew Cab Cummins

[mopardug]

Hi everyone. My husband and I are looking at upgrading our dually.
We currently have a 2004.5 SLT Crew Cab Cummins. It's 2WD -my husband doesn't care much for 4WD's-325 HP, with the 6-speed. It has about 270K miles.
We both like it, but I don't drive a manual transmission.
Sure, it's not perfect, but fits our needs.
We're looking at a '12 Laramie Longhorn Limited. Long box, 4WD, 6-speed auto, 205K, and loaded. Some of the warts: there's tape on the steering wheel, and the left turn signal doesn't cancel, and the cruise doesn't work. There's moisture in the driver's headlight. One of the the marker lights is out on a fender. My husband has never had a 4WD, so he doesn't know how to check one out. And he said that some of these automatic transmissions aren't strong.
Sorry for being long winded, and thanks in advance.
Be safe, and thanks for looking.

 

[mopardug]

On the test drive, when we stopped and put it in 4 high with the round thingy, a light flashed twice, and stayed on. We were on the road, but nothing made noise. When it was turned back to 2WD, it flashed twice, then went out.

 

[HemiSSDart]

On the test drive, when we stopped and put it in 4 high with the round thingy, a light flashed twice, and stayed on. We were on the road, but nothing made noise. When it was turned back to 2WD, it flashed twice, then went out.

That's to tell you it was in 4wd, should have said so and when disengaged the light should go out. There are no good Mopar automatics, but as long as it doesn't slip or chatter there are no issues, most last around 250K miles before something starts to fail. If it did not tow much and you don't plan on doing it either it should last longer. Find out if trans service was ever done and ask if it ever had fuel injector replacement or cleaning. The trans and injectors are the only thing I ever had issues with...

 

[340demon72]

You don't want to be engaging a "part time 4WD" (4 High) on a solid surface! It will put a serious bind in the drive train in a turn and possibly break something. If it indicates "4 Auto" also know as "full time 4WD" that's OK to engage anytime as that has a center differential.

I differ on the Mopar automatics. Pulled a 10K fifth wheel for over 40,000 miles, US and Canadian Rockies, with a 48RE behind a HO Cummins with no issues. It all relates to proper maintenance and no abuse. I know the 2012s have a different setup though.

 

[cojohnso]

Put the truck into 4WD high. Turn the wheel to left or right. Then start off. The truck will hop a bit and you can then feel the 4WD engaged. Do this in 4WD low also to test. This is true for both manual and auto transmissions.

I'm on my 2nd Dodge Cummins 3500, full 8' box 4WD dually, crew cabs. My first was an '03 5.9L. 2nd is '07 6.7L. Both manual 6 speed transmission. Here in Minnesota 4WD is almost a must in winter. The Cummins dually needed to pull 32' gooseneck race trailer. Trailer at max load can weigh 15,000. Both trucks can pull this over extended distance.

 

[HemiSSDart]

You don't want to be engaging a "part time 4WD" (4 High) on a solid surface! It will put a serious bind in the drive train in a turn and possibly break something. If it indicates "4 Auto" also know as "full time 4WD" that's OK to engage anytime as that has a center differential.

I differ on the Mopar automatics. Pulled a 10K fifth wheel for over 40,000 miles, US and Canadian Rockies, with a 48RE behind a HO Cummins with no issues. It all relates to proper maintenance and no abuse. I know the 2012s have a different setup though.

These trucks have the air activated diff and can be put into 4 high at any speed, did it dozens of times with my 04 Cummins with no issues. The owners manual even says that...

 

[Garrett Ellison]

There’s performance transmission in olive hill Ky if you ever did have trouble with the transmission. He used to do mostly Chrysler transmissions before branching out but he does very good work and stands behind it, too. I know from taking a few transmissions there for a friend.