Reliability of LS conversions

[joesgreen67]

Originally Posted by special-K

You can't buy simple new anymore

Sure you can....It's called a crate motor. Last I check there are SEVERAL options to choose from

[Lattimer]

Originally Posted by special-K

I've always found these trucks to be reliable as built. They are old now and if you rebuilt everything to factory spec you'd have the same reliable truck...again. They're actually very reliable still. I'd rather take a long trip in my 41 year old '72 than an '02. One thing for sure,anything breaks down,but when these trucks do you can fix them yourself. I'm not a modern technician with all the modern equipment,so when an LS breaks down it's another story. I've always been able to get my truck home on my own and that says it all. I'd only consider going modern if I could drive my truck daily rather than something now. For any occasional driver I see no benefit. You can't buy simple new anymore

I'm kinda in the same frame of mind. I already have a bunch of computer controlled vehicles....I like not having to deal with that in my Chevy.

[Coley]

The newer LS drivetrains are extremely reliable, capable powerplants...no mistake about it. I love the newer trucks, the technology and the general quality benefit that comes with it.
At least when GM professionally installs them in vehicles that they were fully intended for.
I am running an original series sbc/350 in my '72 and I don't see any return on investment in going the LS route at this point.
When they are retrofitted into another vehicle is when the trouble can start with poor installation practice, missing parts and of course...no technical background or equipment to troubleshoot them, set them...even start them.
I haven't been able to get my head around having to ask a 'tech' guy to come by and start my truck for me then tune it for me.......but thats just me. (Unless I learned the electronics angle myself, which I would be tempted to do).
I imagine having to stand around with my hands in my pockets while he types on the laptop checking system status, etc....kinda' defeats some of the whole idea of the classic vehicle hobby for some reason.
If they shut down on you...and you don't have your reader and your laptop on you, you are a pedestrian and you will have to consider how the local GM dealership will react to fixing it for you...being non-original, modified or similar?
That said, they are really good drivetrains and some of the guys have done excellent work in installing and running them successfully.
My two bits.
Coley

[ls1nova71]

Any vehicle can break down and leave you walking. The same people who say "what if that LS engine quits running" are generally the same people who will get in a new car or truck and think nothing of driving it across country. If you install it right, and don't cut corners, they can be as reliable as any new truck. But you can't halfass it and expect the same. I've personally put over 200k miles on LS swapped vehicles and will never look back at the old carb'd stuff. To me its the 'driveability' part that makes the new engines shine. They always start no matter how cold, altitude doesn't affect them, and they run cooler, which in turn allows you to keep the A/C cranked up even in heavy traffic. Putting one in an older truck makes it so much nicer to drive, it's like having your cake and eating it too!

[mmiddle]

This should not turn into a flame war on newschool/v/old school.

For me, I have built about 20 SBC's over the years. I love them and know them very well. Plus parts are cheap.
However, they all will start leaking oil (2 pc. rear main), they all will start smoking on start-up, they all will run hot. as well as other issues related to carbs and distributors. Now, with that said, yes you can prevent the start-up smoke with special valve seals, but your valve stems and guides will wear fast, Yes you can solve most of the oil leaks, but you have to stay on top of it. Yes you can use a large rad, low temp stat, and electric fans, but if it is bored .040 or more it still will not like Texas summers in traffic.
I love Q-jets, but HATE carbs! The GM HEI is awesome but it still needs regular maintenance.
The LS-x motors fixed all these issues and more. Plus is way more efficent and powerful.

If you love the SBC and want to stay with it, I say Great! they are the second best engine ever produced. If you want to have the very best switch to the LS-x. Life really is greener on this side.
True, the cost-payout is a net lose for sure. If you don't have a factory service manual and hand-held diagnostic scan tool these engines are near imposible to service. But for those willing to venture over the fence we can have all the modern convienences and advantages of a brand new truck with the look and class of old iron.

[67ChevyRedneck]

If I REALLY had the time and money, the best thing to do is put the whole damn truck on a 99+ Silverado frame like Drew did Ride, handling, performance, etc would be a massive improvement.

[mmiddle]

Well, heck ya
Except you would loose the awesome traction of swing-arm rear suspension.

I had a complete doner truck (hit in rear). I plan on using the complete electrical system including cruse, DRL, PL/PW, delay wiper, et.al.

[FL71C10]

About 20 years ago I had a pretty nice 71 GMC that was my daily driver. I sold it and bought a new truck. I remember being tired of the old stuff breaking. Not the major components, but loose window seals, gaskets, rattles, and stuff like that. So I guess the decision is if you do a new motor conversion, you have to bring the rest of the truck up to snuff.

[rcrahn]

Originally Posted by FL71C10

About 20 years ago I had a pretty nice 71 GMC that was my daily driver. I sold it and bought a new truck. I remember being tired of the old stuff breaking. Not the major components, but loose window seals, gaskets, rattles, and stuff like that. So I guess the decision is if you do a new motor conversion, you have to bring the rest of the truck up to snuff.

Excellent point....could not agree more. That's why out project has taken so long. We are going through everything in our LSx powered vehicle. When it's all said and done I could of easily bought a new truck with the money spent - but what fun would that be?????

[mmiddle]

Originally Posted by rcrahn

When it's all said and done I could of easily bought a new truck with the money spent - but what fun would that be?????

Exactly! It's not about the money and time spent. It's about the journey to the destination that makes the destination so nice.

[WickedDirtBag]

Well said! Mmiddle +1
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[67_C-30]

I'm not sure I competely buy the reliability factor of swapping to a LS engine, but there's no doubt they make more power in stock form than any old SBC's. The reason I question the reliability is based on my 2000 Z71 and numerous friends that have these trucks. The engine itself has been great, but I put a $400 fuel pump on it at 60,000, $130 water pump at 70,000, and a $40 thermostat (because its made into the housing) at 90,000. Now I know a lot of people will say that spending $600 in the span of 90,000 isn't bad, but I have had numerous SBC's that went WAY over 100,000 miles after a rebuilt without replacing anything but plugs. Hell, I can rebuild a 350 Chevy for $600. -lol

The parts being much higher for the LS engines offsets a lot of the advantages of doing the swap, IMO. I also think a lot of people confuse reliability and longevity when it comes to doing the LS swap. EFI engines in general last longer than old carb'd SBC's. I have also had more than one TBI 350's that have went over 260K with no problems and seen some over 300K, but compared to the LS engines, they are gutless as far as power goes.

I have considered doing an LS swap and came close to doing it once, but I can't justify the cost on a truck that make be driven 5,000 miles a year. Even if build a SBC that makes the power of a LS engine and gets 10 - 12 MPG, I would never recoup the costs of the LS engine.

I'm not knocking anybody that does the swap, and like I said, there's no doubt it is a better engine than the old SBC. I just don't think it is as cost effective as a lot of people seem to think it is.

[468BIGBLOCK]

i have seen several stock 4.8 and 5.3 in delivery vehicles with 400,000 miles on them and i saw one with 797,000 miles on it, i have never seen a sbc with many miles on it.

[twisty]

my work has all 2500HD service body trucks for field workers, some of those suckers have over 300k on them and get used a ton during a regular work week. the 6.0 is a solid motor, the owner gets the chevy trucks for actual work while us managers get ford F150s. the owner is a ford guy.

i think if i were to want to do an engine upgrade, the LS-x swap would be the way id go. theres many trucks/ vans you could find a decent motor in for cheap enough to make it worth while. we are going to stay I6 250 for a while tho, i like that motor.


edit:
come to think of it, im not sure if those trucks had the6.0 or the 6.6 in them... but i know truck 34, the one i used to drive on occasion had the 8.1 in it. what a beast.