2016 3500 HD Farm truck, frequently tows a 20 ft cattle trailer and a 20+5 gooseneck (roughly Â±24k lbs loaded) loaded with round hay in the summer. Lots of short trips/stop and go driving and quite a bit of other various towing. 39k miles, 2,6xx hours. The truck is still under the 5 yr/100k powertrain warranty. The truck is still running on the factory fill Dex VI, the spin-on was changed and magnet cleaned at 2,000 hours. I think I may do a double drain/fill and filter change soon and then a single drain/fill and filter change every 1,000 hours from here on out, that should be about once per year give or take. I believe GM calls for a 45,000 mile transmission service if the vehicle is operated under severe conditions, but doesn't mention hours. I'd say going nearly 3,000 hours on Dex VI is pushing it. Allison fluid and filter chart I priced three locally available fluid options today, all prices include tax. What would you choose and why? I know that the Allisons do well on most any approved ATF, I'm just looking to hear peoples thoughts. The Starfire is the thinnest of the two Dex VI products I priced, however both are "full synthetic" and GM licensed and approved. 1: Starfire Dexron-VI 12 quart case: $44.15 2: Havoline Full Synthetic Multi-Vehicle ATF 12 quart case $62.70 3: Shell Spirax S6 ATF A295 (Allison Approved) 3-1 gallon jugs $115.96 I also need to change the transfer case and front and rear differentials soon. What do you all think about running TES-295 in the transfer case? As far as I can tell, it specs Dex VI. I'm thinking I should probably stay with Dex VI until the warranty is up. Is the pump rub issue still a problem on these or has that been fixed on newer models? I bought some Starfire full syn 75w-90 for the diffs today. Six quarts was $58.83 including tax, working out to ~$9.81/quart. I could have gotten a better deal on some Supertech, but still not a terrible price and this is all boxed up and sealed, I can be sure this wasn't tampered with. Plus this place gives me great prices on everything else, I like buying from them. Some of the gear oil bottles at my local Walmart are questionable. Plus, Walmart rarely has more than 1-2 quarts of 75w-90 available at a time.