25 Iforce Max MPG and Delayed acceleration

Bought my truck 3 months ago and currently have 7K miles. Lifetime MPG is 14.8 and 60+ % of driving is thruway. Best tank hand calculated was 16.9 and just had a 450 mile rd trip that averaged 15.8. I’ve had 2 6.2 GMC’s (21’ 24’) and both averaged between 17/18 mpg. Also, if you’re on the highway and accelerate to pass, it’s a good 2-3 seconds of hesitation before it’s does anything. Anyone else experiencing this? I’m happy with the truck besides some dumb Toyota features but the MPG’s and delay is frustrating.

 

Get use to it. It's been discussed since the 22 came out and not a big secret. And you will get mixed answers. Yes, I have the same issue, no I dont or I have one of either of the 2 issues.

 

https://www.tundras.com/threads/off...tation-from-stop-issue-s-t-sb-0111-22.106155/

 

What octane gas and oil weight are you running

 

Same fuel mileage with mine.

Also, I still own my Gen2 5.7L and it's so much more responsive than this 3.4L Turbo.
I know Toyota advertises similar HP with the V6 but it must be at a high rpm because it just feels so doggy compared to the 5.7L

Quick google search of dyno results shows;
5.7 giving about 145HP and 280TQ at 2300rpm.
3.4 shows about 110HP and 220TQ at 2300rpm.

Just a massive trade off of torque at the lower rpms .... for an extra +1 or +2 mpg.
Maybe eventually the V6 can create that torque at higher rpms but who's driving, towing, taking off from a light, at 5000 rpms?
I much prefer the power at the low rpms where I do most of my driving. MPG would need to be +4 or +5 mpg to justify such a trade off.
Now factor in the excessive cost of the twin turbo ... and lack of durability. Not at all worth it.

If Toyota offered both engines in the Gen3, I'd venture to guess the 5.7 would be more popular at this point. By a lot.

 

87 and whatever the recommended oil is from the dealer. The delay isn’t the motor, it’s the transmission I think. If you get on it a little, it’s fine. I’ve tried using sport mode because it’s much more responsive (to much for regular driving) but if you’re already moving and put it to the floor, still does nothing for 2-3 seconds. It’s much more frustrating than the MPG’s.

 

I am not a GM guy at all (lost all of my stock in 2009 government buy out) but the 2 6.2 I had with less HP and TQ had no delays. With the tundra, I merge during rush hour, I punch it and feels like you’re going to get hit because it doesn’t go anywhere and then takes off.

 

There is a HUGE amount of electronic buffer built into throttle response on my 2023. Both at low speeds and higher speeds. I was shocked when I got a Shiftpower throttle response controller. It just plugs inline at the gas pedal and a little bluetooth box so I can hook up to my phone. It also has a button you can mount for changing between 4 different accelerator settings. https://shiftpowerusa.com/

The faster settings will kill your gas mileage but it is fun.

It has a bar that changes with the factory acceleration and a bar with the modified acceleration input. The lag is crazy from the factory. Not sure if they did it to be nice to the engine or if it because of the Cafe' standards. It is similar to a Pedal Commander.

I will try to take a few videos when the weather clears up of the difference in the acceleration bars.

It makes a huge difference to get rid of the Turbo lag by actually letting the engine do what it is supposed to do before the turbo kicks in.

 

I read MPG reports like this and I don't get it. I get 21-22 on my suburban "retired commute" (mostly a mix of freeway and mid speed country roads) and on road trips that have a mix of freeway and similar country roads. 2023 non-hybrid on 87 octane. I do have the occasional hesitation, though not as bad as you describe. But then I don't really punch it from a stop, rather roll it on to see if it is hesitating or not first.

 

Was thinking it was way more than that for the 3.4TT, no? Would think the throttle mapping is the cause of what the truck “feels like”. My 2019 5.7 felt a little sluggish unless you really stepped into it, or tapped that Tow/haul button.

 

How many miles on your truck right now? Did you see 21-22 mpg from the very stat or did it kick in later (after XX amount of miles on your engine)? Currently struggling to understand the 'lower than expected" MPGs but hoping for things to (still) improve somewhat (I'm at 9200 miles and 7 months of ownership).

 

Not initially, partly because I got it in January on winter gas. But that summer with 5000+ miles, yes. I drive it gently, which is plenty when you have 389 HP on tap. Currently have ~28,000 miles and running perfectly whilst awaiting my recall engine replacement. I am in the final phase for that with dates still TBD.

 

Thanks for the update. Looks like you're way up there in terms of engine miles (especially when compared to an OP and myself). Looks like there is hope (for better MPG); albeit I wish it came in a bit sooner than that.

 

I call shenanigan's

400 lb-ft of torque at 2000 rpms? ...
Taking off from a stop the turbos wouldn't have even kicked in yet. How they getting 400 lb-ft out of a 3.4 with turbos not spinning??
They must be testing it differently than it actually behaves. Engine out of the truck and turbos spun up 100% .. because my 5.7 snaps your head back if the tires don't break loose.
The dyno chart that I found (using a google search) showed 220 lb-ft at 2300rpm. I'll assume this was rear wheel power.

 

I noticed a little better mpg after 10k. The Michelin defenders got better mileage but the Falkens give a plusher ride. Trade off is 1-2 mpg. Big woop.
Acceleration lag is still there at 35k. I still like it better than my Fords.

 

As weird as it may sound, I had this issue since brand new on my 2010(2nd gen). Eventually secondary air injection pumps failed and I had them repaired under recall. After the repair, I never had any hesitation ever. No idea if this may be in any way related,but just throwing it out there.

Maybe they did some sort of ecu flash while truck was in their possession and that was the actual fix. I don't know.

I learned to drive with this 'quirk' and never actually searched for a fix. When they got my air injection system repaired, this was a welcome surprise! I was like, "no sheet, truck drives better 6 years later than when she was brand new!"

 

@OP - are you in ECO mode? Hybrid in ECO mode sucks @ss.

Want a little responsive? turn it to Sport.

 

Are you running Eco, Normal or Sport?

 

I am getting 19.1 both city and highway. one trick I do is the cruse control and just let the truck drive its self. its helped me most of the time when I check on the highway its right around 21 or so. I have 29,500 on a 24,1794 limited edition

 

Something is wrong with your truck. My 2023 hybrid is INSTANT acceleration. No delay. And I get 22 mpg on the highway, usually average about 19 overall.

 

Yeah.....I really dont pay attention to my mileage.
I knew from the get go it wasnt going to be great and with all the towing I do it's kinda pointless.
When it gets to a quarter I fill it back up.

 

Thanks for all the replies. Truck has 7200 miles. I tried to drive in eco and take it easy as I can but by the time I’m at 150/200 miles on the tank and at 16ish MPG, I give up and put back in normal and drive regular. Yes, radar crusie helps but also sometimes frustrating during morning and evening commute.

My expressway on ramp is on a curve and only about 200’ into a concrete walled 2 lane at rush hour. Even in sport mode, I come up the ramp hot, put it to the floor and almost nothing for 2 seconds and then takes off no problem and runs through the gears. I could put it in manual but it should just work better. Again, I’m not a GM guy (was always ford) but during the pandemic, had to buy what you could get a good price on. 21’ SLT 6.2 and 24’ AT4 6.2. Both dropped 2 or 3 gears and didn’t miss a beat. Had a powerboost F150 loaner for 2500miles between AT4 and Tundra, that also had no hesitation issues.

ultimately, using 87 vs 93, Is significantly cheaper already so MPG is what it is. The performance delays may be the reason to move on sooner than later.

 

It must be a Non-Hybrid thing, when I press it all the way down, she runs like a raped ape!! Very impressed since the day I bought it. I'm between 17-19 mpg's on 87. My last 2 tanks of gas, I've switched to 93 just to see what would happen. I'm getting 21-22 mpg's now. Pretty sure its not worth the extra $1.00 per gallon, but the truck does like it.

 

Didn’t mention if your truck is raised or has larger than OEM tires. Both cost mpgs. My stock 23’ Limited mpg peaked around 15K mi. 18/22 in WA. Had to move back to So Cal and now it’s 14/20. Crap gas here, hilly towns and traffic lights every 1/8th of a mile kill the mpg.

 

Take it to the dealer and have them look at it. Something is not right.

 

24 hybrid here, added a 2" level and 285/60R20 AT tires and MPG dropped from 18.3 to 16.6. I'm about 90% around town, very little highway. Definitely no problem accelerating though, this thing is a rocket!

 

My mpg before and after is similar but with 35" E-load 18's.
Acceleration similar also, and I'm not a hybrid!

Getting 16.5 average now and will still rotate (spin) the 35's easily in Sport mode and Tow modes.
Makes plenty of torque down low.

These things have tiny turbos and spool quickly, and at relatively low rpm.

A minor hesitation from a dead stop or slight rolling stop (likely hasn't downshifted) is normal for these trucks.
A huge lag at any speed is not.

My mpg's continued to improve all the way to 10K miles.

 

I don't want to have to learn how to drive it to get the best MPG.
Eco mode and taking it easy aint for me.
But I still expected better than 15 mpg with 60% highway driving.

In fact according to the trucks readout, highway traveling at 80mph is getting me the worst fuel economy at 10-12 mph.
I get the best mpg at 40-50 mph.

 

I think you're confusing highway and interstate.

Highway speeds are what the EPA estimate stuff goes on, and it's also estimated in perfect conditions. No wind. No hills. 55-65 MPH.

80 MPH is never accounted for in highway mpg because that's not highway.

I know it's dumb, but welcome to marketing.

Also, if the truck in your avatar Is yours, we can clearly see wheels poking out and heavier tires. That's also going to drive the fuel economy down. Is it also lifted?

 

I thought the same thing about not hitting 80 for the test until someone posted this a while back.

https://www.fueleconomy.gov/feg/fe_test_schedules.shtml