DFM install ,do I need to change the oil viscosity

[raul Briones]

going to install the DFM today . my question is do I need to change the oil from 0-20 to 5-30 .
my reason to keep 0-20 is I do not need or want to tow anything , I do not live in mountains area ( N. TX. ) I use my TB for personal use in and around the metro ,or going on a few trips to see grandkids .
I'm figuring all cylinders will get coated since I'm running on all 8 with the DFM . ,planning to drop the oil every 5k miles instead of 10k as noted on GM maintenance .

please explain or help with my line of thinking. is 5-30 better all the way around ? I would still drop oil at 5k with 5-30 .
current milage is 6k on new 2026 TB 5.3 , I already had the oil changed out @ 5k 1st oil change .

 

[Mark L]

I believe the DFM system is installed at the factory, and even if it wasn't, you would not want to install it. If anything you’d want to install a disabler, although my experience with the Range Tech unit was negative.

On the oil viscosity, if you don’t use 0-20, and need any sort of drivetrain warranty work done, they could deny coverage. You are right though that 0-20 is not ideal.

 

[raul Briones]

sorry if I didn't make it clear , it is the Range disabler RA007 .
I just installed it and went through all the steps with the instructions and all went well , well it started anyway went around the block and the stop & start worked like they said / did not stop-turn off !
thanks for input .

 

[Stormin08]

Aside from the government making claims that the OE needs to meet certain C.A.F.E. (mileage) requirements....there is Zero reason to continue 0-20 over 5-30