MrGraff

If your leaving it on auto shift mode and cruise control on inclines then that's your first problem. When Im approaching a good incline, I go into manual mode and let the engine get up in rpms or boost and it usually holds speed or increases speed. That being said, my experience so far towing with the 10spd has been night and day difference vs the old 6 spd.

Well 2 years later, my 6 inch Ultratow hasn't moved! I use the multipro tailgate more than I thought I would. Pulls my utility/boat trailers just about perfectly level.

Took my truck in and was told the pads are on national back order.

Can't say I've ever heard this on mine, 18k miles so far. I'd just crawl under and make sure everything like skid plates are torqued etc.

Looks like I'll have to get this done on mine, they tend to squeal at low speeds especially in drive throughs. Although I'm not sure I want them to just replace pads and do nothing to the rotors.

My experience with the 2020 diesel and exhaust brake is it works well. The biggest difference I've seen is the transmission is much smoother and doesn't result in the jerk or sudden slow down that is perceived with the previous iterations. Its also extremely sensitive to how hard the brake pedal is being pressed. Did my yearly Colorado trip hauling 17000lbs this summer and if anything the exhaust brake worked better than previous generations.

I'm surprised the EPA hasnt cracked down on gas engines, hell I'd love it if they did around my area. Too many kids that are deleting and easily surpassing 100db sound thresholds when they floor it a mile from my house. I've looked at exhausts for my 2020 L5P for one reason, and that reason was to change the direction of the exhaust so it doesnt hit my fifth wheel with regeneration heat. MBRP has one, and banks will have one soon that will be DPF back and will accomplish that. But sound wise, they don't make a difference it is cosmetic and redirectional at best. You would get more engine sound out of your stock L5P by deleting the resonator aka 6.6L Duramax black box under your hood and adding a CAI such as banks or S&B.

Yep nothing will change the sound unless you drop the emissions system, its doable but expensive and very few people will tell you where and what to do.

Mine stickered for 80k, got it for 73k

Towed to Colorado and back from Texas for our yearly vacation trip. Total trip mileage was 1658 miles with 12.5mpg on the computer. Towing to Colorado loaded with 17,300lbs we averaged 10.1mpg @ 68 mph. Towing back to Texas same load we averaged 9.5mpg @ 68 mph. Seems to be about on par with previous gen trucks as far as mileage. However the towing experience was more pleasant and seemed like the truck never ran out of power, the new 10 speeds are excellent.

I felt like my truck was idling rough the other day, turned A/C system off and it went away. As far as regens, haven't ever noticed a dip in rpms at all. Only indicator would be heat from tail pipe and instant mileage tanks.

Bak Revolver X4 on my 2020, I eyeballed the American Work Cover series as well.

Im pretty sure there is a TSB for high DEF usage. Remember seeing something either on these forums or the duramaxforums

My lifetime average is 15.3mpg which is combination of city, towing, and highway for 10,000 miles. Unloaded at 75-78mph I've averaged around 19-20mpg depending on wind. Around town if I dont hammer it I'll get around 14mpg, loaded with my utility trailer and mule pro itll do about 16mpg. My 14k fifth wheel runs about 10.5mpg which is on par with previous generation LML and L5P trucks I've had, and is better on mileage when compared to my 2017 super duty diesel. Mileage wise I see an improvement on unloaded vs my 2019 L5P, other than that it is nearly identical. However performance wise the 2020 is definitely smoother and seems to have more get up and go. I will be doing our yearly tow up to colorado from texas in June and will report back on mileage from that trip as our loaded weight will be in the 17000lb range.

say what? what did I miss? Pretty sure he was asking about oil for a diesel or am I wrong?

If ya want a good tried and true oil for the cheaps, goto walmart and grab the Mobil 1 TurboDieselTruck 5w-40. Past that its pretty much whatever your opinion is, me personally I run Amsoil Signature 5w-40 currently, but will be switching it back over to the 15w-40 oil after my first 10,000 miles. If ya go Amsoil.. its worth every penny to buy the yearly $20 membership because itll save you 20-30 every change.

Mine had vibrations when I bought it... drove it home 550 miles. Next day drove down to my local tire shop and put brand new Michelin LTX AT2s on and its been butter every since. Most good tire shops will give you a decent return on nearly new tires so its a win win to me. Spend 70-80k on a truck and complain about tires, or spend 70-80k and replace the crap stockers and go on down the road.

75 mph? with a 16k fifth wheel? you got more ballz than I do!

This was actually a problem with previous l5p, and was resolved with a computer flash. I bet youd find it wouldnt take much def.

Yep 2020 trucks you dont notice it, about the only thing I think I've noticed is the brakes dont seem as easy to stop the truck during a regen. Mileage is probably the biggest give away your in regen.

Could always try the unhook batteries method let it sit couple of hours unhooked, and then try it out. Almost sounds like transmission related the way your talking.

Same noise on mine with 7200 miles, haven't had any issues other than the random check engine light that will come on and go away randomly after several drive cycles. They changed transmission, injection system, oil cooler, bigger fan/radiator... pretty sure Gale Banks did a comparision video and listed off most of these items. It's a 2020 new platform and powertrain combo so there is bound to be some glitches or hiccups, best thing you can do is get the noises etc recorded at a dealer so if anything ever comes up they have it on record for warranty purposes.

It all comes down to how fast your going pretty much, my 6.5x12 utility trailer with my Mule Pro FXT on it ~ 3000lbs will get 15mpg. My 14.5k fifth wheel doing 65mph will get 9.5 - 10.5mpg depending on wind and roads.

Updated original post to remove Curt from suggestion, thanks for posting that followup!

I'm guessing no, itll still have to drop to around 4-6 inches for the ball to clear the step