With every new truck we learn new things. Here is what I learned this morning. Looking to go with brighter LEDs for driving and fogs, I checked to see what bulb they use. Unfortunately, GM has molded these bulbs right into the light assy so you can no longer just replace a bulb, you have to replace the whole assy. Before you say BS, I looked twice and called a local GM parts house to verify. They are molded in and the hole assy has to be replace when they go bad or if you want go brighter, LED mfg are going to have to start making the whole assy. UGH. I am all about being able to see good at night. While the LEDs are bright, they could certainly be brighter, especially the fog lights. Guess I will be waiting on aftermarket light assy to go brighter. In the meantime, the intellibeam high beam lights works well switching between high and low beam when the truck detects an oncoming vehicle.
Next, the transmission. So as you know the 2020's come out with a new Allison 10 speed tranny. Looking under the truck today to check things over, I noticed there is no external filter like on the older 5 and 6 speed Allisons. Hmm. So I continue looking things over and notice I don't see a trans dipstick. When I looked under the hood, same thing I could not find a transmission dipstick. A check of the manual states it is not usually necessary to check teh trans fluid level. (I beg to differ) The onlyl reason for fluid loss is a trans leak or overheated trans. The vehicle is not equipped with a trans fluid level dipstick. There is a special procedure for checking and changing the trans fluid and should only be conducted by a GM service specialist. Blah, blah, blah. Somewhat disappointing. GM recommends the Dexron ULV Trans fluid.
While looking the 6.6L Duramax Engine Supplement over, I took a quick look at the service recommendations. Here is what I found to be recommended:
Oil and Filter every 7500.
Fuel filter every 22500.
Air Filter, Transmission service every 45000.
No mention of differentials whatsoever.
My plan for the L5P Powertrain is to swap over to AMSOIL full synthetics
when the time comes. Engine oil and filer first. Was looking for a place to install their BMK27 oil filtration bypass setup like on my older Duramax's. Previously we were able to use a aftermarket bracket made by Madjack Diesel. Going to be working with them to see if we can get another bracket for this application.