Is the Chevrolet Silverado 1500/GMC Sierra 1500 3.0L LM2 Duramax Diesel a good reliable diesel engine? I give you my professional opinion as a heavy duty diesel mechanic and review this smaller 3 liter Duramax Engine. I go over the basic mechanic components and some known issues giving you guys my thoughts and overall this seems like a good engine!


I hope you guys are having a wonderful weekend! I thought it was about time I ventured down this path because a couple of you guys have been wanting me to review the 3L Duramax diesel engine in the GMC products like the sierra and Silverado 1500. but these diesel engines are also in the larger SUVs like the suburban.

So this engine has some great features right off the bat. I love the fact that it is an inline 6 engine and not a v6 engine. this makes a great diesel engine and I explain the simple mechanical advantages of an inline 6 engine in the video. I also like that this engine is basically a smaller big truck engine. inline 6 with a single turbo with dual overhead cams is a tried and truth engine design. good to see GM not trying to re-invent the wheel and simply making something reliable.

I don't really like that the block and heads are aluminum but seeing that this diesel engine is in a 1500 it can't be crazy heavy on the front end so I can live with that.

the major thing that caught my eye was that the gear train was at the rear of then engine. there is nothing wrong or weak about this design it just makes for some tough maintenance and sometimes hard to service certain parts. most American made diesel engines put their gear train on the front of the engine to make it easier for service as we usually have hoods that open up in the front.

my hunch is that these 3L diesel engines are going to be sold in the Asian and European markets with their trucks being mostly cab over units thus making these engines easy to service. but not here in north America.

because the gear train is on the rear there is the issues of the oil pump belt. in order to service and inspect this part. the transmission has to be removed which is a huge pain.


00:00 - LM2 3.0 Duramax Diesel
01:03 - Duramax Specs
02:20 - Duramax Engine Components Overview
04:51 - Diesel Inline-6 Engine Advantages
06:09 - 3.0 Duramax Rear Gear Train caution
09:43 - Duramax Long Crank Time/No Start
11:20 - Oil Pump Belt Replacement/inspection Issues
11:53 - Rear Main Seal Issues
12:53 - Injector Issues
14:43 - Fuel Pump Replacement Issues
15:36 - No Emission Related Issues
17:00 - My Conclusion on this Duramax Engine


but other then that I really like the mechanical design of the engine.

Issues
1. Long crank times
- this is the biggest issues these engines face by far. and GM has not really had a good fix for them yet. what usaully fixes of the issues most of the time is replacing the cam shaft position wheel. but to do this job it is very labour intensive and involved removing the whole cab off the frame.

2. the oil pump belt needing transmission to be removed to service it

3. rear main seal leaking

4. injector tips becoming carboned up

5. fuel pump replacement being pre-mature and difficult.


the silver lining is that this modern diesel engine (Duramax LM2) has had little to no emission related component failures or faults which is actually amazing and very impressive from GM

so overall I really like this engine and I do think this could be a very strong running long lasting reliable Duramax diesel engine for these Chevy and GMC trucks!