are chevy or gm diesels bad if there not a duramax?
 

Ive bin looking into buying a diesel problem is my mechanic tells me that the diesels are junk if there not a duramax so give some feedback.

less power, less mods.. thats about it

Pretty much. :c:

It depends on wat you want out of it. I would compare them to a pre powerstroke ford.

yea they dont have many mods out for them and the ones that are dont help that great.

depends on what you want out of it.

Plus points:

Cheap to buy, cheap for replacement parts, decent to good fuel mileage, simple to work on.

Bad points:

PMD is unreliable, blocks have flaws (cracked mains/heads, shearing crankshafts, etc), low power (even "Hopped up" you can only expect around 400ftlbs and 200-ish hp), overheating issues when towing heavy or in mountains, lift pump issues, oil pressure switch issues (powers the lift pump), injectors are only good for about 100,000, etc.

The 6.5 TD trucks are good for about 300,000 and then you're taking your chances. Blowby, injector pumps, etc. Over 350,000 and you're on borrowed time and can hole a piston or die of terminal blowby at any time. Some go further, but very few....

Then there's the fact that even the newest ones are just plain OLD; and old trucks are always more likely to break down on you. Add in front end components, ignition cylinder switches, and any number of other common GMT400 "old age" issues....

There's stuff you can do to them to make them reliable and run well (see my sig), but it's never going to even touch stock Duramax Hp territory.

The PMD issue can be fixed with a quality kit from heath diesel, the cooling issues can be fixed with a newer model pump and heavy duty fan clutch/duramax fan swap, the block can be replaced with a new GEp unit (Redesigned 6.5 named Optimizer 6500, it's in the up armored hummers but it ain't cheap), change out worn injectors, turbo master to replace the failing vacuum wastagte system, high volume lift pump, relay ssytem for the oil pressure switch, etc...

But by then you're pretty far away from one of the main reasons for buying on of the 6.X trucks; cheap purchase price....

I'm not saying buy one or don't buy one. I'm saying go into it with your eyes WIDE open if you do and know what you've got if you do buy one.

My truck runs great and hauls my 8500 lb Trailer anywhere I want. Vantage highway, look out pass, 4th of July, etc, at the speed limit or what traffic is moving at (usually below the speed limit). Flat running it will pull that 8500 lb 9 foot sail at highway speed or better (even with cruise control on) without breaking a sweat. Anything under 65 mph is just in my way, anything traveling 75 mph passes me (but I'm also a slow poke and I'm a firm believer travel trailers shouldn't be moving that fast).

But, my truck is essentially new at this point and for what I have in to it (around 17,000 including purchase price and a brand new optimizer) I could by a decent used Duramax.....I'm just "too far down the rabbit hole" to get out of it now.

Besides, it's reliable (now) and gets the job done. I'm gonna run that sucker for another ten years to get my GD money's worth back out of it!

Assuming we can all still afford to even buy a gallon of diesel by then.......:ouch:

I wouldn't, 7.3 IDI were a dependable engine, 6.9's dependable but not much for power, GM's had reliability issues. :c:

X2 7.3s and 6.9s were great engines

an lb7 even with their injector issues are 3x the engine of a 6.2 or 6.5

Well, that's just a wee bit of an exaggeration.

2001 6.5 is factory rated at 190hp and 380 ftlbs (that 215 Hp 6.5 everyone likes to quote never did exist outside of R&D)

2001 lb7 is factory rated at 300hp and 520 ftlbs.

So it's more like 1.5x the engine, although it wins hands down in durability (injectors aside).

The injectors are another interesting point:

$500 for a set of 6.5 injectors, $1600-2000 for an LB7.

3-4X the cost.

Ouch.

And you will be replacing injectors on both trucks. 6.5's need to be swapped out around 100,000 and LB7's will fail. There's no escape from either, although 6.5's can be pushed longer and the replacement LB7 injectors have been getting better reviews lately (but they still fail).

Like I said before, all depends on what you want the truck to do and your expectations of it.



Cheap to buy, cheap (comparatively) parts and simple to fix - 6.5 TD. But it's never going to be more than a 200HP truck. Buyer beware also; get a bad 6.5 truck and it'll nickle and dime you to death.

More to buy in, more power, TONS more potential and the promise of better reliability - LB7. Buyer beware again: get an LB7 truck that needs work and you better take out a second mortgage.



Yup, it all depends on what you want out of it and your expectations......