So I’m on my phone and for some reason the forum search won’t work for me so I apologize if this is a repost.

My 98 Dakota has a 2.5L in it and the heater core finally went out on me. Original core so I can’t complain! Anywho, I’m just trying to figure out if it is the 2” or the 5/8” sizes core. I assume it is the smaller beings it’s a 4 cylinder but I’ve been wrong when it comes to assuming.

If if anyone can give me some insight or info that would be great!

Thanks for that! Would you happen to know the default size for it? I only ask because oriellys and autozone offer two different sizes.
I would just take it out and bring it down there but it is my only mode of transportation so that option is out of it for me. Thanks!

Update! I bought the 2” core, there is a big difference between the two so I am HOPING this is the one. If not I’m gonna have a bad time! Haha.

Anywho, I’ll be updating this post in hopes it helps someone out with the same problem because there is nothing on the net that has the answer!

That’s great! Thanks man. I went with spectra premium so I’m hoping it’ll work for years to come. Good to know the thin is OEM, though it’s the original 20yo core it did die from clogging so the thicker of the two was the right way to go!
Wish me luck! I only have today to do it so time is of the essence haha.