Report on Chevy/GMC 1500 with 6.2 engine and Max tow pack

[SteveSueMac]

Dznf0g - dumb question here but can you replace 20s with 18s and if so, what are the impacts on load capacity, truck height, adjusting hitch to keep trailer level, odometer and other computer tracking (fuel economy, DEF usage etc)?

I have a 2013 2500 Diesel 4x4 - about 44k miles and when it's time to replace the tires, I'm considering "fatter" aspect ratio 18s but not sure if benefits will justify all costs (not just financials). Thx!

[dznf0g]

Steve, you would, obviously have the cost of the new wheels. I just picked a random tire, Michelin Latitude:

265/65R18 = 2601 max load and 31.5" in diameter $173 on tire Rack
275/55R20 - 2535 max load and 31.8" diameter. $200 on tire rack.

So they are very comparable, and so close in diameter that I wouldn't even pay for the reprogram for the difference in diameter. Price is pretty close now that 20s are more common.

Other brand may have different specs, so check, but it is a pretty seamless transition.

I, quite frankly, can't tell the difference towing, and I have towed with both on Silverados/GMC.

[rodsterinfl]

DC Bruce, your truck sounds nice. There are trucks with higher payloads. I have shared in several posts about my almost ridiculous hunt on the Ford lot with 135 trucks going door to door looking for what seemed forever, a missing truck that came up on the computer that met my configuration need. Needless to say it was listed as a Platinum on the computer and was a Lariat. Duh. I saw payloads as low as 900# all the way up to 2300# payload. Regardless though, you found what you needed as well.

Another thing to consider is the cylinder deactivation technology. I do not know if all of their engines have it but GM admitted to excessive oil use on "high mileage" engines with that technology. In the report they call high mileage 30-40K. It may not be an issue towing but you might want to take an extra gallon of oil on longer trips. As a side note, Honda, who also uses that technology is experiencing the same issue, according to one of the many articles I found in June when shopping the brands. It seems each company has some technology that makes people question dependability whether it be cylinders or turbos.

http://www.tundraheadquarters.com/bl...l-consumption/

[SteveSueMac]

Thanks. I have 265/60R20E tires. At 80 PSI it carries almost 3200#. Not needed - I go around 65 PSI because at 2800# a side, that's plenty of headroom for 4500# on the scales.

If you've done both and can't tell a difference, I'll probably be more inclined to just replace with what I have already. Thanks!

[SteveSueMac]

And my apologies to the OP for the hijack!

[rodsterinfl]

SteveSueMac, there is a website that you input the tire diameter, your final axle ratio and also your final drive (trans) to get the impact of changing tires. Pretty nifty.

Tire Size Calculator

Just digging around on Michelin's website I see that above 18" HD tires or non- P metric tires are few and far between.

[SteveSueMac]

Cool - thanks, Rodster!

[DC Bruce]

I'm aware that Honda has had some oil consumption issues with the variable displacement version of their V-6. That engine used to be available only in FWD versions of the Pilot, and maybe the Accord. Now, I think all Honda V-6s have it.
Regarding GM, since the demise of the ill-fated V-8-6-4 engine offered in the Cadillac decades ago, I wasn't aware that GM offered variable displacement engines in any of its vehicles. The "Ecotec" family of variable displacement engines was introduced with the revised pickups in 2014. These engines, a V-6 and two V-8s, all have cylinder deactivation. It's kind of hard to imagine this being a big deal. My observation is that the 4-cylinder duty cycle is, at most, 50%; and that's highway cruising with an empty truck. Even on non variable displacement engines, I see complaints about oil consumption, probably due to the very light oil now specified for most engines. I'm at 11,000 miles and have not had to add any oil (yes, I'm about due for a change). My BMW, over the 12 years I owned it, consistently used 1 1/2 quarts between oil changes; my Honda Pilot doesn't use any. Really, my bigger concern is GM's use of direct injection, which has proved troublesome in other makes, especially VW. With no gasoline washing the intake valve stems, there has been accumulation of crud from the PCV system that clogs the intake passage. And in first generation BMWs the high pressure fuel pump failed repeatedly due to the ethanol in our gasoline. Interestingly, Chrysler's new 6.4 liter gasoline engine available in the Ram 2500 has variable displacement but no GDI. It also produces less HP and torque than the GM 6.2. I'll keep an eye on things; beginning late October, we're going to weigh anchor and become more or less full timers for a while.

[pappy19]

The Ford F-150 3.5 Ecoboost walked all over the Chevy V-8 on towing tests, you might want a second look.

[phbarnhart]

Originally Posted by pappy19

The Ford F-150 3.5 Ecoboost walked all over the Chevy V-8 on towing tests, you might want a second look.

Sigh, more trolling. No links, no references, no evidence along with a highly subjective term like "walked all over?"

I've not seen a towing test in which the Silverado 6.2 w/8speed and max tow was "walked all over" by the F-150 3.5 ecoboost.

[pappy19]

Here you go-

https://www.youtube.com/watch?v=1y45zPEE4Rs

[gandttimes]

DC Bruce. The GM variable displacement came out before 2014. I have it in my 2008 6L 1500 with Max Tow. No oil problems to date after 138000km.
The 4cyl mode will actually come on while towing our 25ft on the flat with a tailwind. It is so seamless that you have to be watching the DIC to tell.



George

[phbarnhart]

Originally Posted by pappy19

Here you go-

For the sake of completeness, here's the article that went along with that video. The Silverado in question was last year's version with the 6 speed.

I'll ask again, anything with the 8 speed?

[DC Bruce]

The 6-speed in the 2014 GMC/Chevy truck has a poorly chosen set of ratios. That's evident even when you drive the truck empty. With the 5.3 engine, it feels like you are always heavy on the throttle to get the truck to accelerate. The extra power of the 6.2 takes care of that, but TFLT Ike test of the 6.2 with the 6-speed vs the 8-speed in the 2015 model shows the difference between a poorly matched and a properly matched transmission. With the 8-speed, the 6.2 easily matched the Ecoboost towing performance while achieving better fuel economy. Also, unloaded, pickup trucks.com found the 6.2 got substantially better fuel economy than the Ecoboost, which was my experience: 400 miles at 24.9 mpg driving empty between 60-65 mph. The 6.2 has higher rated horsepower and torque than the Ecoboost, although that's probably not true at elevations over 5000 feet, thanks to the turbos in the Ecoboost which can compensate for the altitude. I think both engines are fine for towing any Airstream. As a personal preference, I don't care for the non-linear throttle response of turbocharged engines, although the Ecoboost is better than some. Others think it's fun.

[dznf0g]

Also, the 2015 6.2l is a next Gen engine over the 6 speed version. More torque and hp than the old generation.

[rodsterinfl]

The information on the excessive oil consumption is not opinion but documented and acknowledged by GM. It has to do with deactivating the cylinders. Nothing is mentioned about it not working well but just as an operation it allows oil to spill past the cylinder when deactivated. This may be worse if deactivated during greater loads. I linked the one article. Also the 6.2 2015 uses. 3.42 rear and is rated at 15/21. I cannot believe that it does better than the economist mpg-wise. I do not have my tow mpg yet but I have local city and highway driving 16/23 and that with less than 1000 miles and calculated at the pump not the truck computer

[dznf0g]

Well, I'm no longer on the fence. Today I pays my money and got a 2015 Silverado 6.2L, 8 speed maxtow, doublecab, regular bed. Because of business travel and getting several accessories installed, I won't pick it up until next Thursday, but the deed is done.





Sorry about the turned photos....something wierd with my pic program today.

[crispyboy]

Congratulations on your new TV! That is a nice color - will look good with your trailer. Also very good payload rating on the truck.

[DC Bruce]

You will be happy with this engine and drivetrain. Ours has taken our FC27 from Washington DC to LA in a month. We've pulled 9.5% grades up and down around Death Valley. Best 400 mile average MPG was 13.8; worst was 11.6 bucking a 30 knot headwind and ascending the Rockies.

[DC Bruce]

PS: I have added 1 quart of oil during the trip.