2020_3500HD

I found and attached the tsb from when I had my 2015 truck. It has a chart showing approx crank times associated with different temps.

If the outside temp is cold (can’t remember the exact cut off) the gm di motors will have an extended crank time. I experienced this on my previous truck 2015 half ton and my 2020 6.6 truck does the same. Has to do with making sure proper fuel pressure is built up before firing the injectors. Hope this helps.

I live in Indiana so not too many big grades here but towing into a decent head wind I have not had any problems maintaining speed with it staying in 5th

I got the 3500 for the added payload/5th wheel hitch weight capacity also I have had 15k behind the truck before for about 100 mile tow and didn’t see myself needing anymore power. I for one like the tried and true 6 speed that the truck has and have not found myself in a situation needing more gears. If you go the gm route get the 5th wheel prep package the puck system is very nice to have.

Yes I know the op stated that the dealer in Canada had put that in his truck was trying to advise him to get it changed back to the spec.

I have never found myself needing more power. I too live in Indiana and a couple months back towed a similar weight travel trailer through the Smokey mountains and had no issues maintaining speed on the grades. This is my 2nd truck with the 6l90 transmission and knock on wood neither have given me any troubles. I do agree that axle options would be nice but the 3.73 seems to be a good middle ground for decent fuel mileage unloaded. I too have the 3500 and have not found myself needing more payload capacity. Hope this review helps in your decision making.

I don’t believe that the 6.6 has the resonator due to not having AFM/DFM. I don’t remember seeing one under my truck.

I have a regular cab 1 ton w/t and I find the seats just fine. I agree with MTU get the 18” wheel package better ride and it fills out the wheel wells much better too.

The fluid is in there while parts are being used for the first time right??? Hence “break in”.

Grumpy, why the red line over the amsoil? I am coming up on my 5000 mi get the breakin fluid out change and if you can let me know why? I have always used Amsoil before but am open to others if it is better for my application by the way I have the 6l90 transmission. Thanks in advance

Maxed the truck out the other day hauling dads 5th wheel no issues here. These trucks do their best when around 3500 to 4000 rpm keep it there and have never noticed a lack of power.

I also doubt it would be standard. From my point of view I like the 6 speed be it crude and have its normal gm 6 speed issues it is rock solid and the other 2 I have had were trouble free for 250k plus miles.

I feel the same from time to time but only in 3rd gear. My previous 6.0 truck with the 6l90 would do the same thing and it never missed a beat in the 200k plus I owned it. I am just glad I don’t have the 2-3 flare that my previous truck had since tuning is out of the picture with these new trucks. Hope this info helps.

Yes the 0w20 is thin for our motors. Up there in Canada if you wanted you could use a 0w30 to help with the cold starts but I would be concerned with the 20 weight oil once up to temp. It states right in the owners manual to use either the 5w30 or 0w30 for temps below -20 F

Just got back from a family vacation to the Smokey Mtns with our 36’ TT about 9500 lbs loaded with gear and I didn’t have any oil consumption over the 1000 mi round trip. Towed great and had no power issues with keeping speed up the grades in eastern Tennessee. My truck just turned over 4500 miles on the return trip. On a side note as part of my breakin I drove the truck like I normally would the first 1000 miles and changed out the factory oil fill for 5w30 Mobil extended performance with a wix filter. I had great luck with this combo on my old 6.0 that gave me well over 200,000 trouble free miles. Hoping this new 6.6 will return the same. Let us know what your dealer says on the oil consumption I would be interested in knowing.

I have had it a few time but only during extremely hard braking, my 09 2500 with the 6l90 would do the same and got 250,000 trouble free miles from it.

Did some research if your truck has the factory 245 tires the overall diameter is 31.5”, the 265 tires are 31.6”. Now the 285/65r18 will be 32.6” and the factory 275/70r18 will be 33.7“. Below is a picture of my truck with the factory 18” tires with aftermarket wheels

Also no clearance issues, but his truck is 4wd

I have a 3500 SRW with the 275/70r18 tires. I believe that is the same size if your 2500 had the 18” wheel option too. On my dads 2020 2500 Duramax the dealer was able to re-flash for the change over to the taller diameter 18” tires since he stuck with a size that the truck would have came with stock.

Sorry rears not tears

I have a srw 3500 and the light will come on if the tears are below 60 psi fronts I run at the recommended 60 so I can’t speak for that. The 60 in the rear helped my ride out a bunch and I just bump back up when I tow my equipment trailer.

That is good info to know. I had a 6.0 in my last truck it was an 09 regular cab 2500 I bought new and got my current truck to replace it. I do keep my trucks for the long haul and plan on doing whatever I can to help with the longevity of it. Any recommendations on what can to run? I see lots of guys running the upr on their 6.2 , up for any suggestions. Will be 1000mi here in the next few days and will be getting all the break in fluids out.

If the covers are similar to the other LT motors I have seen lots of guys still catch oil in their cans. I agree if their is something different with the L8T motor it would be interesting to see.

New to the forum but long time GM truck owner. I have a 2020 Silverado 3500 with the 6.6 gas. This is my first DI engine and wanted some input on what if any catch cans are available for this engine. Thanks in advance and sorry if I have posted this in the wrong spot. Tim