new duramax owner with questions...

[dcmsu]

I recently purchased a 2001 2500 HD with the duramax and allison tranny. I am changing all the fluids and filters on it, what would you recommend? Some of my info says that the engine is supposed to use 10w30...that doesn't seem right, and the dealer I talked to says they always use 15w40 Rotella. What should I be using? In summer? Winter?

Also what is the deal with the "bypass" oil filters? Is it really that big of deal or is it just insurance?

I plan on keeping this truck for a long time, so just want to do everything right.

Dan

[chuntag95]

First, welcome to the page.

Second, there is not set or right answer to your questions. I would recommend using the search function, a bunch. Each and every fluid is discussed in pain staking detail at some point in this forum. The list of fluids and filters you should look at are 1. oil (both) 2. transmission (both and don't forget the donut magnet on top) 3. rear differential 4. front differential 5. fuel filter 5. transfer case 6. grease all 11 fittings. More detail on your truck i.e. 4x4 CC existing mods etc. would help us customize the answers more.

As far as your bypass question, I have one and believe they will add life to my truck. Analysis of the oil seems to agree. You can also shorten your change frequency and get the same results. I run synthetic everything. You are required to run systhetic in the rear diff and the front is highly recommended if you live in cold climates. All others are optional. The spec oil weight is 15W-40. Some run 5W-40 Delvac 1 (Mobil Synthetic) others run Series 3000 5W-30 or Heavyduty Diesel 15W-40 from Amsoil and still others Shell Rotella, Delo, etc. etc. etc. Read, learn and make up your own mind, as it is your money in the long run. :D