Diesel Question

[bryan8252]

I have never driven a diesel so I don't have 1st hand knowledge of this. But while going through many threads here, I have come across some who complain that the diesel seems to lag when attempting to pass on the interstate. Or is sluggish when getting on the gas. That seems to be contradictory to what I heard, that the diesel makes it's torque and power early. I would think when you step on the gas and it downshifts, you would get more power which would make passing another vehicle seem effortless.

What am I missing?

 

[martinajm]

When you mash the gas and the transmission downshifts, RPM's go up and you get into the better power band of the gas engines. Horsepower is what you need for quick acceleration. Both the 5.3 and the 6.2 have higher available HP than the 3.0. Does the 3.0 drive like a sports car - NO. However, I don't have any complaints over the 75k miles that I have on mine.

 

[bryan8252]

Thank you for the explanation.

 

[89Suburban]

@StephenPT

 

[Padraig]

No complaints on my 2023 Duramax acceleration. Oh and I have a heavy foot.

Padraig

 

[JayceeP]

This is my only complaint. My 2024 Yukon XL diesel is sluggish when you mash the pedal at highway speeds. It’s almost better if you keep the RPM’s mid-range.

Around town, accelerating to highway speed… lots of pep. But if you’re cruising at 60mph or a bit less on a single lane highway and you want to pass a transport truck or a couple of cars going slow so that you can do 65mph. Floor the gas pedal to pass them and you will see that it’s sluggish. myself, I would sure to have lots of space to oncoming traffic and don’t take chances until you understand how much pull you really have on the highway.

Having said that, I have no regrets. The torque is incredible and you can cruise up and down big hills on the highway at 75mph and the transmission won’t even downshift.

Again, the only point where you’ll notice the lack of horsepower is mashing the pedal at highway speed. It’s night and day different over the F150 2.7 eco boost I just traded in, and even more pronounced with the 3.5 ecoboost in my new F-150.

You sure will enjoy getting 20-27mpg day in and day out in your diesel though .

 

[bryan8252]

This is my only complaint. My 2024 Yukon XL diesel is sluggish when you mash the pedal at highway speeds. It’s almost better if you keep the RPM’s mid-range.

Around town, accelerating to highway speed… lots of pep. But if you’re cruising at 60mph or a bit less on a single lane highway and you want to pass a transport truck or a couple of cars going slow so that you can do 65mph. Floor the gas pedal to pass them and you will see that it’s sluggish. myself, I would sure to have lots of space to oncoming traffic and don’t take chances until you understand how much pull you really have on the highway.

Having said that, I have no regrets. The torque is incredible and you can cruise up and down big hills on the highway at 75mph and the transmission won’t even downshift.

Again, the only point where you’ll notice the lack of horsepower is mashing the pedal at highway speed. It’s night and day different over the F150 2.7 eco boost I just traded in, and even more pronounced with the 3.5 ecoboost in my new F-150.

You sure will enjoy getting 20-27mpg day in and day out in your diesel though .

While I would love to get that type of mileage, what you just described is my concern. That would take some getting used to, especially since I have driven a V8 for the past 14 years.

Thank you for this.

 

[Stbentoak]

Passing people at 80MPH is about only .01% of my time with it. All other days it is far superior in normal day driving and a tank of fuel lasts at least twice as long. The only engine of choice for this big vehicle.

 

[RST Dana]

Once upon a while I sat behind a 400HP Cummins with a GVW of 80k quite frequently. Talk about lag when you press the long skinny pedal! But, when I was back in command of either my Corvette or Blazer, both over 400 horses, I felt like Grumpy Jenkins!

 

[JayceeP]

While I would love to get that type of mileage, what you just described is my concern. That would take some getting used to, especially since I have driven a V8 for the past 14 years.

Thank you for this.

I’d encourage you to test drive. It’s not that bad but anyone saying acceleration is not a bit sluggish at highway speeds (when you mash the pedal) has a different view than me. It’s a great engine and has a ton of torque. The diesel pulls this thing like a champ. I have zero regrets especially after this highway run to pick up my dog this morning. I’ll convert for you Americans. It was just over 17 miles. 15 of which was highway and of that highway a lot of it was 75mph. Some light hills up and down. Door to door I got 27mpg. And in my experience, the on board computer is accurate within 0.1-0.2mpg every tank so these are real true numbers. I have hand calculated every tank over 5,000miles fyi.

I’d be lucky to get 18mpg on that same trip with the 5.3 V8.

 

[bryan8252]

I’ll convert for you Americans.

Lmao.... I for one appreciate that. And I plan on going for a test drive to see for myself before deciding between the 6.2 and the diesel.

 

[B-train]

This is my only complaint. My 2024 Yukon XL diesel is sluggish when you mash the pedal at highway speeds. It’s almost better if you keep the RPM’s mid-range.

Around town, accelerating to highway speed… lots of pep. But if you’re cruising at 60mph or a bit less on a single lane highway and you want to pass a transport truck or a couple of cars going slow so that you can do 65mph. Floor the gas pedal to pass them and you will see that it’s sluggish. myself, I would sure to have lots of space to oncoming traffic and don’t take chances until you understand how much pull you really have on the highway.

Having said that, I have no regrets. The torque is incredible and you can cruise up and down big hills on the highway at 75mph and the transmission won’t even downshift.

Again, the only point where you’ll notice the lack of horsepower is mashing the pedal at highway speed. It’s night and day different over the F150 2.7 eco boost I just traded in, and even more pronounced with the 3.5 ecoboost in my new F-150.

You sure will enjoy getting 20-27mpg day in and day out in your diesel though .

You can thank our glorious EPA for your sluggish response when the pedal gets mashed. Too much soot will be produced (EEk!!!!), so the calibration gives power at a rate deemed "clean." My brand new 2023 F450 work truck was the same way.........utterly pathetic if you needed to pass or get out of your own way. The de-rating was clearly evident.

Look towards our northern neighbor for companies that help diesels go on a diet and regain what they should have had from the start.

 

[SNWMBL]

I read the same thing prior to purchasing and I think it accelerates just fine.

 

[StephenPT]

I don't have any experience with the 6.2, but I've never once said "I wish I have more power." We tow a 5K travel trailer and if I need to pass a semi on a grade, there's always more power available. The Duramax is a perfect powertrain for these land yachts. Take it easy on the speed and the MPG numbers will blow your mind.

 

[bryan8252]

Just finished test driving a Sierra equipped with the diesel engine. I know it isn't the same as being in a Yukon XL, but I did not find any issues driving through town nor out on the highway. And I made sure to cruise along at 70-75 and then try to pass some vehicles. Personally, the engine did not seem sluggish to me and easily got up to speed to get around a line of vehicles.

To the sale person's credit, they did inform me of issues with the 6.2 and that they had a few come back for full engine replacements. While not getting too detailed, they mentioned a problem with the oil circulation.

Also, the manager told me that they wouldn't be able to order a Yukon with the diesel until May. When I previously heard "spring", that is March or April. So I am a bit disappointed it may be longer than I expected. But holding out for that engine, at least for me, seems to be the right thing to do.

 

[Pressureangle]

I have older diesels, '94 Chevy 6.5 turbo. They're pigs at highway speed, but get 17mpg compared to 11 in my gas trucks.
If you need to accelerate to pass on the interstate, diesels are not for you. They're great pulling a load or for mileage at steady state, but passing is just not their forte.
They'll keep speed even with a load, but they don't pick up speed quickly.

 

[StephenPT]

Just finished test driving a Sierra equipped with the diesel engine. I know it isn't the same as being in a Yukon XL, but I did not find any issues driving through town nor out on the highway. And I made sure to cruise along at 70-75 and then try to pass some vehicles. Personally, the engine did not seem sluggish to me and easily got up to speed to get around a line of vehicles.

To the sale person's credit, they did inform me of issues with the 6.2 and that they had a few come back for full engine replacements. While not getting too detailed, they mentioned a problem with the oil circulation.

Also, the manager told me that they wouldn't be able to order a Yukon with the diesel until May. When I previously heard "spring", that is March or April. So I am a bit disappointed it may be longer than I expected. But holding out for that engine, at least for me, seems to be the right thing to do.

Sounds like you found a good dealer/salesman if they honestly admitted to you the issues with the 6.2. Most dealers are “deaf” to issues and it’s always the first time they’ve heard of something if a customer brings it up.

My only guess on the delay in diesel orders is capacity constraints as they wind down LM2 production and go to 100% LZ0. The LZ0 has been out for awhile now in the pickup trucks and the only thing I’ve heard about it is that DEF consumption rate is higher than previous model years (LM2).

The LZ0 added a second DEF injector and is setup to meet more stringent NOx emissions.

 

[bryan8252]

Sounds like you found a good dealer/salesman if they honestly admitted to you the issues with the 6.2. Most dealers are “deaf” to issues and it’s always the first time they’ve heard of something if a customer brings it up.

My only guess on the delay in diesel orders is capacity constraints as they wind down LM2 production and go to 100% LZ0. The LZ0 has been out for awhile now in the pickup trucks and the only thing I’ve heard about it is that DEF consumption rate is higher than previous model years (LM2).

The LZ0 added a second DEF injector and is setup to meet more stringent NOx emissions.

Do you carry DEF with you regularly? Just on long trips? Or not all all?

 

[B-train]

Do you carry DEF with you regularly? Just on long trips? Or not all all?

We have gone past the carrying extra fuel stage in this world......now we carry extra emissions fluid.

 

[Stbentoak]

I probably have use 10-12.5 gal in total in 3.5 years..... 34K miles. It's really a non-issue.
If I was on a 1200-mile trip towing... then maybe, but you could always get it a at dispenser then if usage was high.