Had a engine fire burned wiring harness around area of brake master cyl. Nothing serious but insurance didn't want to deal with it. So totaled it out because parts like engine harness and others not available. It's a 1998 dodge 3500 ram 12 valve 4x4, automatic SLT excellent shape with 144k miles on it. Engine was replaced at 122K former owner towed quite a bit no porometer and blew number 6 cyl. So without informing owner the diesel shop replaced with a 1997 rebuilt 12 valve. When he got the bill just told them to keep i t. I bought it at a auction for $15K 15 years ago . Previous owner contacted me and gave me all the upgrade and prior repair information. I'm now going on 86 failing eye sight and arthritis and been working on tractors and vehicles since I was nine and decided to have it repaired by a local diesel shop who has had it since November 2025 finally said they didn't want to deal with it so I'm picking it up and attempting to do it myself. I have two complete engine harness but not for this vehicle. It's a no brainer to fix if I hold together. If you can send pictures of your firewall on your 98 dodge ram and any help would be appreciated.

 

A ‘98 12V is a VERY special version of these trucks it is a 3 month ONLY wire harness for the 12V .
They changed a ton of stuff in ‘98 getting ready for the 24V motor. It was not quite ready at first so they kept the 12V going for 3 months in the new ‘98. This made a special wire harness JUST for the 12V ‘98. NO other wire harness for a 2nd gen Dodge will be plug and play. Be VERY careful picking up wire harnesses for a ‘98 12V.

I own one so I know. I bought a ‘98.0 12v 5 speed 4x4 quad cab short bed, years ago, great truck, but has some rare parts on it. I also have a spare wire harness for every bit of a ‘98 12v truck. Let me know if you would Iike to discuss buying it.

 

rogoknite, just so you know I have delt with Oliver quite a bit over the years and he is a very honest and upstanding man to deal with and has a huge wealth of knowledge about these first and second gen trucks, as well as the parts for them.

 

Thanks Vern,

Just trying to help out as most people are shocked, if not straight up tell me I am wrong, when I tell them the ‘98.0 wiring harness is a 3 month only set up.

Using a ‘97 or 98.5 wiring will end up with hours of wasted time and it still will not work.

People that want to swap out the less reliable 24V motor for the tried and true 12V out of their ‘98.5-‘02 trucks search high and low for the ‘98.0 12V wiring, as it makes the swap plug and play.