Hypermiling the Chevy Tahoe 6.0L v8 40MPG! :O

[Tahoe_Hybrid]

Originally Posted by ksa8907

I believe the engine must run at higher speeds even when not accelerating to run the trans fluid pump.

These engines don't have a lean burn, but the cam is special and allows LIVC, late intake valve closing.

Yes it does

it has v4-DFCO (Fuel shut off) you can watch the O2 sensors hit 0.00 to 0.235 volts that means 100%-75% oxygen... you can actually drive in this mode I found a glitch in the computer system to regenerate,DFCO and speed up on the down hills at the same time . even if it's very very slight


No shell anymore they scammed me , I just use Chevron only

the BEST i have gotten was 31MPG so far around town. so far

55.00% increase over the base EPA mpg
138.46% over the base EPA of a normal 6.0L suburban 1500 (same year/front end)

best on the highway is 26.9mpg (variable speeds)
35% increase over the base EPA mpg
92.85% over the base EPA of a normal 6.0L suburban 1500 (same year/front end)


I think we need to move onto Aero mods as i hit the cap of what hypermile can do

[oil pan 4]

There's lots of aero mods you can do. Pick and choose the ones you like.

[ksa8907]

Originally Posted by Tahoe_Hybrid

Yes it does

it has v4-DFCO (Fuel shut off) you can watch the O2 sensors hit 0.00 to 0.235 volts that means 100%-75% oxygen... you can actually drive in this mode I found a glitch in the computer system to regenerate,DFCO and speed up on the down hills at the same time . even if it's very very slight


No shell anymore they scammed me , I just use Chevron only

the BEST i have gotten was 31MPG so far around town. so far

55.00% increase over the base EPA mpg
138.46% over the base EPA of a normal 6.0L suburban 1500 (same year/front end)

best on the highway is 26.9mpg (variable speeds)
35% increase over the base EPA mpg
92.85% over the base EPA of a normal 6.0L suburban 1500 (same year/front end)


I think we need to move onto Aero mods as i hit the cap of what hypermile can do

You would need a wideband to verify, I am very curious however I would still contend it does not have a "lean burn".

[Tahoe_Hybrid]

Originally Posted by ksa8907

You would need a wideband to verify, I am very curious however I would still contend it does not have a "lean burn".

got a p0420/430 fuel trim spiked to +34 as well as the short/long term at 900rpm both banks f unky computer issue i'm going to disconnect the battery and resit the connections and clean them

the positive cable is damaged for sure on the battery it was acting funky the engine was acting like it had a vacuum leak reving up and down...

[jazclrint]

Originally Posted by oil pan 4

Our 2018 hybrid hyundai sonata will switch over to electric at about 80mph on level ground.
Too bad chevy uses such tiny motors.

Going to do any mods?

It's not the motors. There are 2 60kW motors in the transmission. It's the tiny NiMH battery pack, They can only get 35k (47hp) out of it. But the torque is good still.

[Isaac Zachary]

Originally Posted by Tahoe_Hybrid

I use 91 Octane Fuel as it keeps 4th gear longer with minimal down shift to 3rd gear on The freeway

I didn't know this vehicle was turbocharged.

I don't notice any difference in my Avalon between 85 and 91 R+M/2 octane.

[ksa8907]

Originally Posted by Isaac Zachary

I didn't know this vehicle was turbocharged.

I don't notice any difference in my Avalon between 85 and 91 R+M/2 octane.

definitely not turbocharged. Though it is 10.7:1 with port injection. I can attest, it does operate better on 91+ than 87 octane, particularly when it's above 90°F.

Are you trolling? ...cause you're at 7700 ft altitude, of course you don't notice a difference.

[Isaac Zachary]

Originally Posted by ksa8907

definitely not turbocharged. Though it is 10.7:1 with port injection. I can attest, it does operate better on 91+ than 87 octane, particularly when it's above 90°F.

Are you trolling? ...cause you're at 7700 ft altitude, of course you don't notice a difference.

If it runs better with 91 octane with a measily 10.7:1 CR even at sea level, I'd say there's something wrong with atomization more than anything. Either that or it's coked up with carbon.

[Tahoe_Hybrid]

Originally Posted by Isaac Zachary

I didn't know this vehicle was turbocharged.

I don't notice any difference in my Avalon between 85 and 91 R+M/2 octane.

the engine runs at 2250rpm at 80mph in 6th? gear equivalent [EVT mode]

a downshift to 3rd would be 4500rpm ish

i used a disable chip for AFM btw


at 40mph it's at 1,000-1025rpm.....

see:

https://www.youtube.com/watch?v=zNkz...el=punker4real

[Isaac Zachary]

I don't see why lower octane would cause it to downshift unless it's severly affected by something else.

On the other hand, it kind of defeats the purpose of getting better fuel mileage if you have to pay for premium fuel.

Octane shouldn't be much of a difference at lower engine loads. At lower loads engine timing and power output have more to do with just finding the right ballance. At idle you should be able to advance the timing as much as you want and not cause any detonation.

Where octane is important is at higher engine loads, like when you have the pedal to the metal. But shifting from 4th to 3rd at part load because of using the recommended octane instead of high octane fuel for forced induction engines sounds fishy.