Where can you buy the oil and filter for a 2021 Ram 2500 with a 6.4 Liter Hemi ?

I bought my 2021 Ram 2500 in September 2021. It was my first brand new truck and when I saw what the dealer was charging for oil changes, I knew there was no way I was going to have them work on my truck – I’ve always done my own work but because this may well be my one and only new truck, I knew I better do some homework.

First off, I did not want to void my warranty. In talking with the dealership their recommendation was that I only use Dodge/Mopar brand oil filters and Pennzoil Platinum 0w40 engine oil plus I should keep a log of when I changed the oil, filter and with what. Okay I thought – I can do that.

This is a great example of where the Internet and the web can just drive you nuts. If you search about what oil and filter to use, you will get just a ton of search results with guys offering up their weird home brew concoctions, using different weights, brands, etc. That was all fine and dandy but I did not want to void my warranty or give a dealership some excuse to charge me because I didn’t use the approved oil.

Which filter does it use?

If you want to stick with factory parts to avoid warranty headaches, you need the Mopar MO-339 filter. I am using the 04892339AB but am told there is now an AC part number. Regardless of the letters, I would not be concerned if searching turned up an AA, AB or AC. The main thing is that the correct model is MO-339.

This is the correct model number – Mopar MO-339. Sure, there are other quality brands of filters out there such as Wix but my intent is to use Mopar filters until the warranty expires. Then I will move to Wix or whoever is best at that time.
FCA is Fiat Chrysler Automobiles. They are now owned by Stellantis – just FYI. The part number is 04892339AB. The last two letters reflect minor revisions to the base numeric part. For example, 04892339AA would have been a previous version of the part. Odds are it would work ok if you find it. I always go for the most current part number I can find because usually they are trying to improve/fix design issues. The AB series started in 2019. I saw an AA filter that was marked 2009-2011 and recently read there is an AC series but I have not seen it personally.

Where can you find the Pennzoil Ultra Platinum Full Synthetic 0W40 Oil?

You are going to need 7 quarts of oil if you change the filter and I always change the oil and the filter. I am used to walking into Autozone, O’Reilly’s or Walmart and buying oil. They do not carry this weird Pennzoil “Ultra Platinum Full Synthetic” 0W40 that Dodge was specifying. Apparently there were some office politics about switching to Pennzoil and to lock people into using Pennzoil plus being more likely to go to the dealership for oil changes they (I’m not entirely sure who “they” are but will blame both Dodge and Pennzoil) – they came up with this odd spec that really wasn’t required. Stuff like that irritates the hell out of me – they could have specified something else and made it easier for all of us.

At any rate, as mentioned, I am sticking with what Dodge specifies through the warranty period. The dealership will usually sell it but do you know where I found it and at a far better price? Amazon – yeah, Amazon. It’s the cheapest and most convenient source I have found and is also why you will find thousands of reviews. Again, remember you will need 7 quarts.

With the supply chain and economy having so many issues, I bought four cases (there are 6 quarts per case). They showed up at my door the next day – it was great!

Quick comment on my experience so far

My first oil change some time late last year was quite an experience. The oil filter had “factory installed” printed on it and boy, it did not want to come off. I wound up using a vise-grip type oil filter wrench to get a good enough hold to finally break the seal and spin it off.

I just did my second oil change getting ready for Winter and rotated the tires also [click here for a post about how to do that the easy way]. I figured I would take a minute and share with you where to buy the filter and oil from and hope this helps you out.

The filter is located just to the left of the bottom of the lower engine’s crank pully. An end cap filter wrench/socket makes changes really easy. For the first one, the factory installer went nuts either torquing it down or the seal stuck to the block – I’m not sure which it was but I had to really crank down with a locking oil filter wrench to get it off.
A 76/14 (76mm with 14 flutes) oil filter end cap socket is the size you need. Mine is made by Lisle and their stuff tends to be really good. Definitely get one for going forward. Mine could not break the filter lose the first time but it wasn’t the socket’s fault – the filter’s flutes rounded over it was on so hard.

By the way, the torque spec for the oil drain plug is 20 foot pounds. Now I know some guys just feel how tight to go by hand and I did that for over 30 years but now do to nerve and muscle damage, I can’t tell how tight I am pulling so I torque to spec – totally up to you.


Note, I have to buy all of my parts – nothing here was paid for by sponsors, etc. I do make a small amount if you click on an ad and buy something but that is it. You’re getting my real opinion on stuff.

If you find this post useful, please share the link on Facebook, with your friends, etc. Your support is much appreciated and if you have any feedback, please email me at info@roninsgrips.com. Please note that for links to other websites, I may be paid via an affiliate program such as Avantlink, Impact, Amazon and eBay.