Which Duramax is BEST? L5P vs LML vs LMM 0-60 + Fuel Economy Test! (SURPRISING RESULTS)

After picking up the 2009 LMM Duramax from Tennessee a few weeks ago, I've been very curious to see how it compares to my 2023 L5P. It just so happens Kyle has an LML truck so we decided to compare all 3! This will be the first of at least two videos comparing the trucks. Today we test unloaded fuel economy and 0-60 acceleration!
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[@richrules]

TOWING TEST is NEXT! What else should we compare on these 3 trucks?

[@theglitch99]

How much better the truck that is pre Def runs.... unfortunately the Def is killing all diesel engines!

[@JohnRyanCahill]

Love this. I have a 2020 gmc 2500hd denali... its a beast towing our 10k camper. What about throwing in a lbz or lb7 to test also.

[@corry685]

Stopping

[@christopherhawn831]

LMM baby! I bought one new in ‘09 and that truck was an absolute beast.

[@theglitch99]

My grandma drives that truck w/it turnt up to 500hp. She loves her powa! Rolling coal all over town!!

[@darreng2639]

I have 08 lmm I owned it 12 yrs now awesome truck no issues what so ever

[@donnieallen656]

How many miles ? And , Is it deleted ?

[@darreng2639]

@@donnieallen656 200,000 and yes its deleted

[@user-bc8tp8nr7b]

I have a 08 lmm 350,000 on it fass 165 with efi live and get 16 around town 23-26 on highway. Towns my skid steer and mini ex 5 days a week with no problem

[@greggaona2647]

My 08 lmm has 335,000 and runs like a top!

[@tyler7146]

@@greggaona2647deleted or stock?

[@greggaona2647]

@@tyler7146 deleted. Glow plugs changed out at 200k

[@Upracefan]

The LMM numbers are especially impressive considering the extra load from McD’s! 😂

[@tthepikester]

LMM pre DEF! I have a 2008 2500HD with only 150,000 miles and does anything I ask. Will care for it until I bury it, will prolly outlast me.

[@donaldsteere645]

I have a 08 gmc 2500 hd only has 107k on it I can say I take care of it and it’s almost same condition.maybe a couple of extra scrapes on the paint but I will say I have driven this all over and will easily take it cross country without a concern only thing I have done to it is leveling kit and 33’s on it they are so reliable .

[@user-yg1dt4dn2j]

My ‘21 l5p had quite a few issues until I deleted it and now it gets better mileage and hasn’t had any more issues

[@TheRealEricRose]

Love the l5p when there deleted!

[@user-yg1dt4dn2j]

@@TheRealEricRose yeah they sound super good

[@tortelini87]

What mpg do you see around town and highway?

[@user-yg1dt4dn2j]

@@tortelini87 I’ve got 21.5 highway but the average is about 12.5 because I’m pulling trailers most of the time

[@marctaft3661]

I dont have any of these trucks but I am really enjoying this comparison. Thanks guys.

[@richrules]

Glad you like them!

[@charlesswearengin2404]

I have an 08 LMM 3500hd 134k, Fass pump HSP all around Except egr is factory. PPE pans oil and trans 5/8 coolant lines w/Mishimoto transmission cooler, averaged 23 going to KC and back. Motor is completely stock I've got the 3" down not installed wanting to get a new turbo for even better boost and economy. I'm keeping my LMM till the day I die! No rust, interior is like that 09 constantly getting comments FYI, PULLS LIKE A BEAST.. 😊 And not spending money on DEF.

[@kevinryan3241]

Great video

[@marka1712]

Cool video and interesting for sure. Can’t wait to see the towing comparison. I’d pick an old truck every time myself. My 03 lb7 is not stock but I have less than $30k in it with having a trans rebuild with suncoast stage 5 parts and a triple disc tc. Same exact style start I do 5.2 0-60 with 33/12.50s. I have only pulled 12k load but it pulled it fine. Fuel mileage sucks though, 15ish empty but I don’t set cruise at 60 ever🤣🤣🤣

[@mken4740]

I love my 18 L5P Denali.

[@flashyfernando3819]

I have a 2008 GMC Sierra 2500 LMM....and i love it!!!!....no issues...just a delete and stock tune....and its perfect. I got the exact same slt with tan interier😂

[@robbystewart8088]

I love both trucks, check the GVWR and tow capacity of the 09 from the door stickers.

[@365AdventureCo.]

I had a 2016 LML and heard so many stories about the CP4 / snapping the crank so I got my 2017 L5P deleted / tuned gets 20 highway 17 city on a 120 tune

[@c0c0asauce]

I had guessed 8.5 0-60 on the 09 as well. I expected it to be competitive but not THAT competitive. I'm not surprised by the MPG though. That body style is actually quite efficient.

[@chuckvedder1227]

I have a Duraburb with an 08 LMM and Alison trans. It's a tank. Open road cruising it gets 20-22 MPG. I didn't hear it mentioned, but if there is a difference in the axle gear ratios, then the mpg and 0-60 isn't a fair comparison. Technically you would have to include the trans gear ratio, diff gear ratio, and tire diameters to make the comparison, but nobody going to change the tire sizes so they all have the exact same overall ratio. Still fun to watch.

[@keithcring8011]

Great content idea. I have an LML

[@robbovay8324]

Rich that truck looks like the truck R3 took to sick week if so what a great friend . If not nice truck

[@TimewithCal]

Nice trucks guys! Good review. I’m wondering is the 09 having less emissions crap on it helped with the mpg?

[@richrules]

I think it being physically smaller was the main thing. It still has its own emissions system that isn’t the best.

[@robertwyant9580]

Only one off those trucks takes def as off now seeing a little coal roll out and the sound of exhaust I’m not buying it 😂

[@Velislide]

Diesel foams a lot when filling, it can kick the pump off randomly towards the top. You definitely need to do more miles to get accurate readings.

[@jeffwrightsman7797]

Are they all the same trim level? The trim levels have more sound deadening material as they get higher levels. My 13 Denali is super quiet compared to a lower level trim.

[@codyrogers190]

The banks derringer and pedal monster are well worth the money for the 23. In my opinion no 6 speed is going to tow like the 10 spd in the 20 plus. The problem with using so little fuel and trying to judge mileage is the amount of foam will shut the pump off at different times.. so unless you over fill it you're not gonna be very accurate

[@richrules]

It's relative; using the same method on all 3 still give the nod to better fuel economy from the LMM.

[@leociesielski4154]

I have 2 08 duramax they both are great they both tow my heavy 35 ft pj one has 420k mi on it and the other has 290k mi they both r tuned and deleted all the way no problem one is a 2500hd crew long and the other is a 3500hd dually crew long have more power than anything with the right tunes the heaviest I have hauled so far was 32,000 combined and on that trip I lost the trailer breaks but the truck handed it so good

[@L.O.C.1990]

09 is a beautiful truck

[@jmj267]

This is almost like TFL truck channel. Gas pumping should use the 2 click top off method after 30 seconds rest.

[@500whpSTI]

I’ve got both an LML and an LMM, 170,000mi on the LML and 470,000 on the LMM. The LMM has been more reliable than I could have ever imagined. The LML is mechanically stock with EZlink tuning and the LMM is straight piped with EFI live. LML gets me about 16mpg and LMM 20mpg.

[@dandeslandes3258]

Love all diesel trucks but the new ones are hard to beat! I'd keep both

[@timAA205]

Duramax tuner/ calibrated power. Fantastic compliant tunes. Probably the best Without question.

[@happygnome4620]

LMM baby!

[@bieniek56]

I have a tuned LB7 with 270k and a 2020 L5P tuned with 60k. I'd have to say working daily I'd take the L5P, you can't beat the creature comforts. But I absolutely love both. The new one has some frikin snort tho but the ole LB7 rips too. I appreciate both in their own way. Both tow 15k lbs with ease and milage wise I'd give it to the L5P because of stock tires vs aftermarket on the lb7

[@Harveyleonard621]

What tuners are you using? We have a banks now and don’t seem like much of a difference

[@bieniek56]

@@Harveyleonard621 motor ops

[@tayalyn08]

I think the only benefit the LML and LMM have over the L5P is the true Allison 1000 trans. That 10 speed has a lot to prove if it’s going to stand up to its predecessor.

[@Brin.K]

Or he coulda got a 17’-19’ and got the best of both worlds, L5P with an Allison A1000 trans 6spd

[@tayalyn08]

@@Brin.K Absolutely I own a 16LML and a 18 L5P the Allison 1000 is an amazing transmission that’s why I think the new 10 speed has some big shoes to fill.

[@Brin.K]

@@tayalyn08 I agree completely and tbh I want to give General Motors a generation or 2 before I chase after the 10spd, let them work all the kinks out first.

[@TonyGabriele46]

I love Gmc Sierra L5P and LML and Lmm Duramax Love Ram Cummins Truck and Ford Powerstroke Truck Rich Rules

[@dylanbutler7804]

Depends on the setting the smallest distance average on the lml and L5p is over 25 miles and you guys only drove 21 so not the best test. Thanks for testing them.

[@RobertGrant1971]

Keep them both!

[@richrules]

I wish!

[@avioncamper]

Keep the 23. That's a fine ride. How did you put 38k on the truck in one year? Any progress on the Seebold? Spring is round the corner. Have a great week.

[@richrules]

Been across the country! Multiple trips to Oklahoma, Tennessee, been to Missouri, Florida. Get driven everywhere!

[@NWI_Steel]

That's wild. 38k at say 15mpg at $4/gallon is $10k in fuel for the year

[@richrules]

@@NWI_SteelI’ve been compiling things for tax purposes and seeing that number kind of hurt 🤣

[@jamesphilli8464]

I have rode in a Cadillac down that road you drove on and it felt as rough as it looked in those trucks

[@rockriver15]

Lmm baby❤

[@dustin4866]

Was your 23 trans leak at the torque converter? My buddies started leaking at 5k then dealer fixed now again leaking around 8k again

[@richrules]

Yeah the seal on the front cover

[@sleddheadxp800r]

17mpg is about right for the 10 speed truck the 17-19 6 speed L5P get way better mpg and the seats are more comfortable too.

[@patricksgarageandhobbies4820]

L5P is a great engine!

[@shrapnelsbunker736]

Just puttin it out there... The badillac needs to make an appearance at the Frankenmuth car show next fall....

[@richrules]

Solid possibility of that

[@berkeleyclubbeveragesinc.8445]

I have a lmm I love it

[@Harveyleonard621]

My pops has the extended cab 08 LMM that runs pretty good but his is only averaging 12.7… what is a good tuner he can get that adds good power and better fuel Mileage?? He has a Banks tuner in it now and it don’t help for shit.. don’t really even seem like a power difference.

[@fishingwithayden9305]

Denali in high trim ltzs had heated annd cooled in gmt 900s

[@oscr01]

I thought your 23 was a denali in the first few videos when you got it. Did you get a different one?

[@richrules]

Nope never had a Denali!

[@burnoutking0712]

Put some tow mirrors on the 09 Rich, would look way better

[@alangolat2907]

07 LBZ Classic bought in 2011 as of today 318000 clicks on the ol’dometer heading for 1 million. Should take 27 more years to hit it. Wouldn’t have any other truck….till death do us part.

[@SparkZ1420]

The 07-13 trucks were pieces though. Do not miss my 08 GMC

[@awesomesaucetv8624]

you definitely got a defective one

[@williammeyer8661]

Lmm’s are great trucks

[@bryanbreon7361]

Lmm needs compounds small fuel and a trans an send it

[@haydenroyer]

Throw some kryptonite products on the front end of that 09 and some fresh shocks and enjoy that 09! It'll tighten that front end up tremendously and the shocks, you would be surprised how much it improves the ride

[@mr4x4s]

Looks a lot like a loaner pickup another new channel used to tow some toys to Florida and back 😜

[@NWI_Steel]

You need glasses

[@tylertomczak2273]

23 L5p most definitely! Tune it and it will be stupid crazy

[@kevintaylor9249]

I'm not a diesel guy but, even I know the "predef detuned" older stuff perform better. The EPA adds are the difference. We also know that the new trucks are capable of better performance but, only if you defeat all the EPA BS... I know you know this...😉

[@Bobbyd603]

Lmm is probably tuned work at dealership and never seen those numbers on 09 and there a lot lighter

[@jacobkorte4832]

Sell the 23 and "build" the 09... eventually the motor tune exhaust wheels tires with airbags

[@Fast1two]

Put a Banks pedal monster and derringer and that 23 will wake the f up. Lol

[@kevinryan3241]

The 23 is definitely a better truck all the way around but it’s also medium duty capable which the 09 is just a pick up truck also the 23 is going to give you emission issues sooner than later I’ve seen more than a few in the shop for weeks because of the emission issues the 09 delete and enjoy being paid off.

[@dredgenyor1674]

the LLY is the best😏

[@vandersnickmcduffle7333]

Are you all going to do collabs with R3? Not sure if ya'll still get along, that's not my business. Just wondering.

[@P-J-W-777]

Kept saying the DEF systems hurt the fuel economy. The DPF definitely hurt them. You’d be amazed what the fuel economy is without all of that crap.

[@t.l.robinson2162]

Sell the '23 and use part of the money for '09 upgrades.

[@DJHunt89]

Take 6 months of payments on that L5P and put it towards that LMM. Then you will have a beast.

[@jake279]

You missing out on 2024 redesign

[@movingearth3726]

You can’t say it’s off because how do you know you stopped the pump at the same gallons that were in the tank as the last one …. Foam does trip the nozzle you can’t do that unless you had exact measurements of fuel sorry I don’t believe it mine says 400 to Emily and I’ll pull early 430 plus till I’m empty soooooo

[@Cnester313]

LB7 is king!!!!!

[@user-cp1vb5pe6b]

It's not tuned. My dad had an 08 and he never had a bit of issues with it.

[@joelentine1905]

The 09 os alot lighter than the l5p if Im not mistaken

[@janamaro5894]

L5P and LMM are both reliable engines.

[@fordman89lx4]

The lbz is the best duramax.

[@KG-ed9eq]

Hard to beat a LBZ

[@bluchevy01]

I still say get rid of the new one build the old one. A mild build so it's still reliable.

[@bustinyanutz4195]

I'd keep the 2023 unless you put a 1,000 WHP and 2,000 ft lbs of torque from a boosted 12 valve Cummins.

[@tomcampbell8931]

Try to get an average off of a 25 mile trip lol😂. Hell my mustang could average 25 if I based it off that 😆.

[@bartlettff]

Let's goooo

[@TheCarhartt1]

Lmm wins all day

[@caynedohner4080]

Keep the 2023

[@JohnRyanCahill]

Just remember #notadenali 😂

[@jonp1116]

Sell the ‘23 before the transmission goes out and build the 09!

[@chriscota1635]

New 10L1000 is not that expensive from the dealership. Sucks they aren’t reliable like the 6speeds. But I have a 94 Japanese sports car that cost more to replace the manual transmission. The 10L1000 does seem to go out fairly early when towing heavy and frequently though

[@mechanictaft4848]

Yea but 09 you put a tuner and that will last forever compared to the 23 pos garbage

[@MrKeithJ2]

Looks like you guys are driving 127, rich rules baby!

[@richrules]

Little bit east of that 😉

[@cybermavrik]

lbz

[@hunterklemz0597]

Thats what happens when you let the epa touch shit

[@thmike]

Less power and lighter truck is gonna get better mpgs!

[@richrules]

The lighter part I definitely agree with

[@MixinGasGarage]

Keep the 23. More reliable, time is money, and it’s a tax right off on your business

[@mini_max8725]

LML is junk. Crank breaking, head gaskets, pistons crack, cp4. LMM is good because it’s identically mechanically to an LBZ. And the l5p is a monster. L5P>LMM and LML in the dumpster, LLY was the best! Until l5p came out,

[@gagefriedrichs]

Dude knows nothing about cp3 cp4 or the hp4 injection pump

[@user-mr5rg1dg4i]

As sombody that's owned all of them....the l5p is the best out of the box. And with losing some parts....it's not even close.

[@jaronvaughn4520]

That 09 is about 1,000 lbs lighter than the 15 and 23 and is for sure a lot more aerodynamic. I’ve had 2 06 models and they got better fuel mileage than my 14 lml.