2008 Chevrolet Suburban 4x4. Need help calculating light mods.

[mpg_numbers_guy]

Originally Posted by fusion210

This is something I had no idea of. What happens?

Do the cylinders that aren't firing cool down while being supplied oil, let more oil by and then burn it when they're reactivated?

Pretty much, from what I understand of it. Here's a link that specifically addresses the oil consumption of the 5.3L in the Tahoe: https://www.gmpartsonline.net/blog/e...tion-solutions

My dad works at a Honda dealership, and he's also said that the Accords and Odysseys with the V6 and cylinder deactivation have oil burning problems as they age. This link discusses some of Honda's oil consumption issues with their V6 engines with cylinder deactivation:
Excessive Oil Consumption - Honda Problems

[Enviro]

Originally Posted by Hersbird

I doubt the fuel economy gauge is accurate in 4cylinder mode. I know my 5.7 Hemi with that feature was way off, as was the scan tool I had running with the Torque app. I also agree with the above, lower it but keep the air dam and still skin the bottom. Removing the air dam isn't going to decrease frontal aera one bit as everything else under there, like the rear axle, is just as low and the rear axle wont move an inch with a lowering kit.

I just checked it at the gas station and it was just about dead on overall so I don't have any reason to believe it is off. Chevy makes some weirdly efficient trucks for some reason. The suburban has a CD in the mid .3's and will most likely be around the lower .3's when I am done modding it.

[Enviro]

Originally Posted by oil pan 4

If you want to lower it then lower it.
Air dams versus belly pans would appear that belly pans are slightly better for substantially far more work, materials and time. Plus if you put a good belly pan on there it might boil the gas in the fuel tank.
The air dam gives the most benefit for the least time and materials with the least undesirable side effects.

I might just do a partial flat belly then and leave the gas tank exposed.

[Tahoe_Hybrid]

Originally Posted by Enviro

I just checked it at the gas station and it was just about dead on overall so I don't have any reason to believe it is off. Chevy makes some weirdly efficient trucks for some reason. The suburban has a CD in the mid .3's and will most likely be around the lower .3's when I am done modding it.

it's 0.367



if you install the Hybrid Body Kit
it will drop it to 0.340 same as a Geo Metro hatchback


I wind tunned my Tahoe with rain and dirty water spots left

tell you were the wind turbulence issues are ..


i'll take some photos of areas that need " to be dealt with"

[Hersbird]

Originally Posted by Enviro

I just checked it at the gas station and it was just about dead on overall so I don't have any reason to believe it is off. Chevy makes some weirdly efficient trucks for some reason. The suburban has a CD in the mid .3's and will most likely be around the lower .3's when I am done modding it.

It's not wierd, it's just physics. I don't think it's going to get
a 30mpg tank no matter what you do. Good aerodynamics are one thing, massive frontal aera is another. I think 25mpg at 60 mph and under would be possible but not 30. I've had a few Suburbans and although never one newer than 2005. I do know my smaller minivan with a very efficient latest generation v6 will only barely touch 30 mpg at 60 mph. Already lower, very clean underbelly, highway gearing, 6 speeds and only 2wd. We did have a 2003 5.3 4x4 Burb that would hit 22mpg around 60, my current 2500hd 2001 was getting only 15.2 mpg across Washington but running 70 mph with 7 people and gear and it has 235,000 miles on it and aggressive AT tires, the 6.0 and heavy duty everything. My 5.7 hemi Chrylser Aspen, slightly smaller than a Suburban but just as aerodynamic, with 5 speed and cylinder deactivation would just barely get 20 mpg at 55-60 and running 70 deactivation never happened and was more like 17-18 mpg. I do agree as full size real SUVs go, the Suburban is the way to go. A Tahoe does no better but gives up room and seems to cost more on the used market. The Fords just haven't been reliable, and Dodge just only made them a few years 2003-2009. The Toyotas are overpriced and do about the worst on FE for some reason. That said, craigslist or publicsurplus.com is full of under $1500 cars that will get 30 mpg all day. Suburbans will always be available when you do really need one and 2 years down the road the $1500 car will still bring $1500 and the same Suburban you sell will be $3000 less to replace.

[Tahoe_Hybrid]

Originally Posted by Hersbird

It's not wierd, it's just physics. I don't think it's going to get
a 30mpg tank no matter what you do. Good aerodynamics are one thing, massive frontal aera is another. I think 25mpg at 60 mph and under would be possible but not 30. I've had a few Suburbans and although never one newer than 2005. I do know my smaller minivan with a very efficient latest generation v6 will only barely touch 30 mpg at 60 mph. Already lower, very clean underbelly, highway gearing, 6 speeds and only 2wd. We did have a 2003 5.3 4x4 Burb that would hit 22mpg around 60, my current 2500hd 2001 was getting only 15.2 mpg across Washington but running 70 mph with 7 people and gear and it has 235,000 miles on it and aggressive AT tires, the 6.0 and heavy duty everything. My 5.7 hemi Chrylser Aspen, slightly smaller than a Suburban but just as aerodynamic, with 5 speed and cylinder deactivation would just barely get 20 mpg at 55-60 and running 70 deactivation never happened and was more like 17-18 mpg. I do agree as full size real SUVs go, the Suburban is the way to go. A Tahoe does no better but gives up room and seems to cost more on the used market. The Fords just haven't been reliable, and Dodge just only made them a few years 2003-2009. The Toyotas are overpriced and do about the worst on FE for some reason. That said, craigslist or publicsurplus.com is full of under $1500 cars that will get 30 mpg all day. Suburbans will always be available when you do really need one and 2 years down the road the $1500 car will still bring $1500 and the same Suburban you sell will be $3000 less to replace.

Hitting 40MPG in the city with my Tahoe RWD with the 6.0L engine
Running aggressive tires...

Hybrid of course as I have figured out how to game the system (ECU) to MAXIMIZE city MPG....
40 city US-MPG /27 US-MPG Highway


on the Sub vs Tahoe cost

it's down to the size and the ease of parking it that is why it's more popular (and why i bought one)


He is chasing a pipe dream... esp since 4x4 is an automatically a penalty MPG wise

[Shaneajanderson]

Originally Posted by Enviro

I would love to buy a 2010 or newer Prius but I am budgeting super hard and will need my Suburban to build my house, which is what I am saving for.

No disrespect, but by the time you do the mods you are talking about you could buy a decent 4 cyl car which will easily outdo your suburban on fuel economy and maintenance costs. There's just only so fuel efficient a 5000 pound 4x4 brick with a V8 can be.

[Hersbird]

Originally Posted by Tahoe_Hybrid

Hitting 40MPG in the city with my Tahoe RWD with the 6.0L engine
Running aggressive tires...

Hybrid of course as I have figured out how to game the system (ECU) to MAXIMIZE city MPG....
40 city US-MPG /27 US-MPG Highway


on the Sub vs Tahoe cost

it's down to the size and the ease of parking it that is why it's more popular (and why i bought one)


He is chasing a pipe dream... esp since 4x4 is an automatically a penalty MPG wise

CITY is the key, add a plug in charger and you could do unlimited MPG as they can go pure electric up to 30 mph for a limited time. The Hybrid Pacifica is a better choice as it can go up to 80 mph pure electric with a range over 30 miles and has the built in plug in charger that recharges in 2 hours on 240 volts. You could own a Pacifica and never put gas in it. They used the 6.0 in the hybrid GM because it runs on the Atkinson cycle so without the motor assist it makes less power and torque than the 5.3. The differences between a 5.3 and 6.0 (or a 4.8, 5.3, 5.7, 6.0, 6.2, and 7.0 for that matter) are all internal. They are all LS small block Chevys. The Cd is the same a a 30 year old Geo metro, but it's not like a 30 year old Geo was the pinnacle of aerodynamics. That said Cd is one thing, but CdA is where you combine the Cd with the frontal aera to get actual drag, and the Metro probably beats the tahoe by 1/2. Here is where a Suburban does just as well if not better (compared to Tahoe) as the frontal aera is the same but the added length usually helps settle the air better. I almost bought a used Aspen hybrid which shared the same electric motors, battery, and CVT with the Tahoe hybrid but they sold it just before I got there. No huge deal, we found a normal one for $10,000 less which probably saved more in the long run as we only kept it 3 years. We also needed the 9500 pound tow rating the standard one had.

[aardvarcus]

Well, here is some hopefully helpful advice for your project.

Good job pulling off the roof rack, I never cared for them nor the desire to add them and load them with heavy cargo raising your center of gravity.

You mentioned building a house, I hope you are planning to insulate it well to reduce the amount of energy used by the house. (Note you don't have to use new/fancy methods to have a well insulated house.) I built my own house (myself, not paying others to work) so I understand about needing a capable vehicle to move materials, often with limited notice.

I did the small commuter car/ heavy truck thing for a while, ended up not being as big a benefit due to constantly taking the truck because I needed to haul more than the car could. I moved on to trying to build a reasonable MPG vehicle capable of hauling a reasonable amount. I end up using less fuel on an average weekly basis overall this way.

I have a build thread on here, 1994 K2500 4x4 Suburban. I was daily driving it a 55 mile each way commute, getting mid-24s for MPG. Mine is not nearly as aerodynamic as yours (yet, big things planned). I am temporarily driving a 4Runner until I can pull off a few more mods and get some of the creature comforts installed in the Suburban.

I would suggest reinstalling the air dam, mine handles much better with the air dam. I made a custom conveyor belt air dam for mine, higher in the middle but lower at the edges to kick more air away from the tires. Tire deflectors will help you. The exhaust is a huge issue with the belly pan, be extremely careful or you will create an oven (with your gas tank inside). I eventually plan to belly pan mine everywhere except the exhaust, but am running an air dam until I have time to pull that off as it will be a large undertaking.

Edit:
I would also suggest keeping the mirrors (or installing smaller mirrors) but add a panoramic backup camera and/or passenger blindspot camera. The comments about the Tahoe Hybrid parts are a good suggestion if they fit yours, the ones that can easily be sourced and swapped especially any that improve aero in the rear should be on your short list.

[Enviro]

Originally Posted by Tahoe_Hybrid

it's 0.367



if you install the Hybrid Body Kit
it will drop it to 0.340 same as a Geo Metro hatchback


I wind tunned my Tahoe with rain and dirty water spots left

tell you were the wind turbulence issues are ..


i'll take some photos of areas that need " to be dealt with"

OMG yes please!!!