Fuel efficiency drop in newer models ?

[viven44]

Nice. What's the story with the Ford truck? Is that an F250?

It’s a 1986 F350 4x4 4-speed w/460 w/Dana 60 front axle, all factory stock , 1 owner since 89’, 169k miles, came from Oregon. Bought from daughter in TX after dad passed away. I could have drove it back 200 miles but didn’t have a driver.

 

[viven44]

Good thing I don't live in Texas. I'd have a yard full of vehicles!

I live on a 1/4 acre and have about 4 classics, and 2 daily drivers. Wife is mighty pleased

 

[strutaeng]

It’s a 1986 F350 4x4 4-speed w/460 w/Dana 60 front axle, all factory stock , 1 owner since 89’, 169k miles, came from Oregon. Bought from daughter in TX after dad passed away. I could have drove it back 200 miles but didn’t have a driver.

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Very nice! What are your plans for it?

I too have a old vehicle "dealership" at my house LoL

2020 3500 Express passenger van
2013 Chrysler minivan
2006 Suburban 2500 2wd
2004 Suburban 2500 4x4 (project Suburban)
2000 K3500 CCLB SRW (dump-run/weekender work truck)
1999 Silverado 1500

Wife says I have too many old trucks. SMH

 

[viven44]

Nice, you are really in the thick of GMT800... The daily drivers are in my signature, but really until I got the 02' Yukon I alternated between my 84 F350 (2WD) and 1978 Bronco. It is nice to get double digit mpg in the city on the 02' Yukon

I'm tired of big restorations (like my 78 Bronco!), that I why I paid good money for something original and unrestored and in regular use here. This truck really doesn't need anything... Only needs R134a conversion and really minor things here and there ...

 

[vincentc77]

Anyone notice the he has the Z71 package? Tire rolling resistance has to come into play - just not sure how much that would impact since Ive never had the Z71 or similar AT tires on any of my rigs.

 

[JayceeP]

Hi all,

We just bought a 2024 Suburban Z71 with the 5.3 and 10 speed transmission... now before I go further, I am not very concerned about fuel efficiency (otherwise we wouldn't have bought the vehicle) I am simply making observations and expressing some level of disappointment in engineering decisions that haven't benefited everyone...

Compared to the 2018 with the 5.3 and 6 speed transmission we used to have we are noting that real world fuel efficiency

- in the city is slightly better in the newer model (13mpg vs 15mpg)
- on the highway we are noticing a significant drop in fuel efficiency. On our 2018 if we drove it well we averaged 26-27 mpg whereas on the 2024, we are maxing out at about 18 mpg... (when we had the Range AFM dongle plugged in on the 2018 we still averaged about 24-25mpg...)

The low-end torque was also honestly better with the 2018 with the 6-speed transmission.

The official ratings (from fueleconomy.gov) are definitely supportive of our observations that the outgoing models were better in fuel efficiency.

No change in Tow ratings vs the outgoing model

I loved the 6-speed and it was easy to service and maintain (relatively easily dropping pan, change filter, change fluid, monitor via dipstick). The 10-speed's oil pan is right under the exhaust and looks like both the driver and passenger side manifolds have to be undone to even drop the pan.

I don't see any articles or discussion over this. Being in the engineer profession myself, I am not seeing a better "Figure of merit" with the new technology. Hopefully somebody can educate me on what I am missing.

Not to contradict you but I don’t know in what world I’d expect to get 26-27mpg in a V8 Chev Suburban. Maybe very flat, perfectly paved country roads doing 55mph…. But that is in no way a realistic highway number if you’re driving over 70mph.

 

[viven44]

Not to contradict you but I don’t know in what world I’d expect to get 26-27mpg in a V8 Chev Suburban. Maybe very flat, perfectly paved country roads doing 55mph…. But that is in no way a realistic highway number if you’re driving over 70mph.

Unless the estimate shown by the computer was incorrect that's what we saw on the highway. It was 2WD, not sure if that helped. My wife drove it most of the time and she is a very conservative driver. I can guarantee that I have never seen below 24mpg in the trips I took.... but then again, I never confirmed that with actual fuel up data.