TrueBlue

Given your chart GB, and the anecdotes we've seen here of what I think were 10L80 transmissions running consistently at 200 degrees and higher under light-ish towing loads I'm very pleased that mine stays around 145, even in high ambient temps. Of course the proof will be in the pudding when I actually pull one of my trailers, but at this point it appears that I won't see temps in the "dangerous" ranges for my tranny.

Thanks for the detailed explanation. I'm old enough to remember the old vehicles with transmissions that were either not cooled at all, or run through the bottom of the radiator. Sometimes it appears that much like my latter days in my job as a computer analyst in a fortune 500 company, insofar as our vehicles are concerned testing has moved over into the production environment. And we are the testers

Thanks, so being a different beast altogether, anyone know what the "optimal" temp is for the 10L80/90 for proper shifting?

I have the 10L80 gas transmission. It rides at 145 or just a tad higher in the heat. Haven't towed with it yet. Both of my trailers are lightweight, 900 - 1500lbs empty, so I won't be pulling a whole lot of weight with it when I do pull them. But given this statement, "Ideal temps for automatic transmissions to do their job the best is 175-220F", what does that mean for our gasser trannies? Are they not operating at ideal temp? Or do those temps only apply to the 10L90 on the HD trucks?

No pictures. Possible that the brand could make a difference, though I've always thought the numbers tell the story. All I know for sure is that his tires sure looked good.

I would take it to a very able mechanic/technician that you trust and have them plug a good reader into it, as well as evaluate it front to back, top to bottom. Check Carfax. Neither is a guarantee but it would be good to learn everything you can about its prior life. Also, for that amount of money you can probably buy new, and if possible pick up an extended warranty. Then you'll be warranteed for several years and/or many miles.

Been Using these for years

So, if they can create an app for your cellphone that can show you detailed information about the fuel use in your truck and the remainder thereof, why not just put that functionality in the truck to begin with? I think I know, but regardless of why, they really should.

Well, if the can catches any vapor at all, that it turns into liquid, it should amount to a lesser buildup on the valves. Or so I would think. I just don't know to what extent it might amount to. I installed a catch can on my 2018 Fat Boy, and I did have to empty it from time to time. That small amount would have been sent straight into the throttle body, so I know it was doing at least some good. I would think the same would apply here. Some of us like to hedge our bets. Especially given that we don't get to write our "investment" off like some companies do.

You might want to talk to a mechanic about that. if the PCV inlet to the airbox happens to be upstream of the MAP sensor it might cause an issue. Or possibly if putting the catch can in line between the valve cover and the intake might result in what would amount to a vacuum leak?

Given the fact that there appears to be two separate routes for the vapors to travel back to the intake valves I would tend to agree. If there was only one, and the can was in line, between the pan and the intake I would be much more inclined to equip my truck with one of these. There is no doubt that direct injection does result in carbon build-up on the valves. What is needed is a way to avoid this entirely. As well as that which comes from unburned oil vapors. But until the next technological break-through I guess we're stuck with the issue, or both. The thought of tearing the top end of my engine apart in order to blast the valves with walnuts or some such is not a welcome one.

I've read a few. I just don't think my question has been answered. I find it hard to understand how the catch can can be capturing all of the vapor when it isn't in line with the PCV.

I have the stock 275/60R20 tires on my truck. I've been contemplating a change for awhile now. The other day I followed a late model GMC Sierra into the Home Depot parking lot to ask him what he was running on his truck, which had immediately caught my eye, and that I liked the looks of very much. His tires looked wider than mine, and lower in profile. Turned out he was running 275/55R20 tires on his. I was amazed that they looked so much different than mine. Just 1/2" shorter profile, just over 1" in total height and the same width, but it was very noticeable. Both trucks were equipped with original factory wheels. Different brand than my tires, but I think that the numbers are what tells the story, not the manufacturer/model of the tire itself. Right?

Question on this. If the Separator is between the intake manifold and the left valve cover, but the PCV valve hooks directly from the right valve cover to the air intake tube, isn't that latter process still adding oil vapor from the oil pan/crankcase into the intake valves?

Thank you Sir. In my case I think this is a good thing. Do you happen to know whether or not DCFC is deactivated, along with DFM when in L9?