LMM or LML

Digmax

Member
Jan 23, 2016
289
2
18
Well all I know is my lml will run circles around my old duramaxs, like no comparison and all where stock trans, all tuned, The lml has 135,000 miles now and I need a convertor, it's starting to chatter. I really watch it close and as far as the trans itself goes I don't believe it has ever slipped. Now I believe what your saying as far as lasting after you slip it. The feeling I get is if it ever starts slipping it's gonna be shot. I slipped my lly trans on a daily basis almost and it just kept going. So yea lml trans may not last as long but it will hold more power. My uneducated seat of pants opinion lol.
 

Lmmduramax94

New member
Nov 6, 2016
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The LML's don't hold more power; they limp less because the TCM pulls back much more power than it used to. I have seen many LML's come into my shop with destroyed clutches and never limped because the TCM can pull a lot of power out of the system.

So out of the 2, which would you say has a "stronger" tranny?
 

S Phinney

Active member
Aug 15, 2008
4,011
18
28
Quncy, Fl
So out of the 2, which would you say has a "stronger" tranny?



If I were picking on the tranny alone it would be the lmm. There are too many other positives on the LML for a daily driver. If you are looking performance potential I would go lmm based on tuning strength.


Sent from my iPhone using Tapatalk
 

Lmmduramax94

New member
Nov 6, 2016
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Like often do cp4s go out? I'd definitely rather buy the lml but I don't want to throw an exhaust and a rather basic tuner and have to replace the cp4 with cp3. That's alot of money off the bat
 

Blackmax123

Member
Aug 2, 2014
683
1
18
central Pennsylvania
From everything I've seen or read the cp4 failures are really hit and miss and no way to really tell when it's gonna die. I've read some guys having 100,000 + with now issues and I've read guys having 15,000 and it has failed. Too many variables to really tell how long it will last.

Also just so you know switch onot the fly tuning is available for the lml's now. But their tunes are more expensive.

It's gonna cost effective down to your needs and wants
My lmm is a nice truck, bought my lml to haul the lmm to truck pulls. My lml drives way nicer than my lmm ever did. I'm currently @114k on my lml no issues yet. But I do plan on a cp3 swap this summer.
 

Lmmduramax94

New member
Nov 6, 2016
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So there's no signs of it? Just one day you'll go to start it and boom its not gonna work haha


From everything I've seen or read the cp4 failures are really hit and miss and no way to really tell when it's gonna die. I've read some guys having 100,000 + with now issues and I've read guys having 15,000 and it has failed. Too many variables to really tell how long it will last.

Also just so you know switch onot the fly tuning is available for the lml's now. But their tunes are more expensive.

It's gonna cost effective down to your needs and wants
My lmm is a nice truck, bought my lml to haul the lmm to truck pulls. My lml drives way nicer than my lmm ever did. I'm currently @114k on my lml no issues yet. But I do plan on a cp3 swap this summer.
 

kiwilml

Member
Nov 4, 2015
454
0
16
So there's no signs of it? Just one day you'll go to start it and boom its not gonna work haha
More like it'll be running fine one second and the next it'll die for seemingly no reason..

But I wouldn't worry about it, just make sure you always get fuel from a known good source helps out I believe..
 

oscyjack

New member
May 7, 2016
775
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0
Northeast
Lml trans will hold better than lmm... also frame and front suspension is good bit better

frame is different, not necessarily better FYI. Fully boxed does not equate to better, careful with the kool-aid :D

I and many others prefer an open C channel. There is a reason the medium duty trucks are still running them :)

OP, not that you should listen to me. But I had a '15 LML that I traded for my 2008 LMM. I wanted more play money and the LML generational improvements didn't seem to be worth it to me. The LML does have beefier brakes and an "upgraded" hydroboost. Fully boxed frame doesn't really mean much other than tougher repairs if needed on the frame sections themselves, and less compliant ride from the frame. The front end is still needs the same mods, the driveline is much the same transmission aside, the shocks are still garbage, the interior is 99% the same. Some slight aesthetic differences on the exterior.

For me, the LML meant an additional $1,500ish on a CP3 conversion. That's $1,500 I would have to earn in addition in order to get the trans/turbo within the same timeline, not to mention most LML's were approx 4-5k more than a comparable LMM. The difference in price and not needing a CP3 conversion, allowed me to pay for and install all the mods on my truck this far without spending anything beyond what I had planned with the LML. At the end of the day I will be sitting at approx $42k with trans/turbo/deletes/tunes/sound system/aesthetic preferences/driveline R&R/new wheels/tires/built front end and good lube front to back. I paid $30k for my LMM LT crew cab with 50k this past March. I paid $43k for my 15 LML dbl cab LTZ and drove it for a month before switching to the LMM. Similar costs but in my opinion a vastly beefier truck.
 
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