5.3 LH6 engine sources

[C-ya]

Well, since I'm considering selling my '05 with a 5.3, I decided to investigate the costs of replacing the engine as it is about the perfect vehicle for me. Has anyone used or heard anything about Promar Precision Engine? link They are a bit cheaper for a long block than others by about $400. Jegs/ATK is also an option link as is Blackwater Engines link

I'm going to ask my usual garage and one down the street what they will charge for an R&R and then see if it makes sense to do it myself. My brother-in-law has a cherry picker, but I don't know what else needs to come out or be removed/moved to get the engine out and back in. I would replace the starter and motor mounts whoever does the work. Power steering rack has already been replaced since my ownership, and trans was rebuilt about 30K miles ago. Water pump is not that old but it may be worth changing while everything is accessible.

My biggest concern is the oil pan and the thru-shaft. It shouldn't scare me but I'm not sure the correct order to remove them. I have the Haynes manual plus the manuals from @Mooseman 's sig so I know I could do it. I would just need to do some research. I have no idea what an engine swap would cost but I'm guessing $1K minimum.

 

[Mooseman]

So why are you considering replacing the engine? As a pre-failure thing? If it's still running well, drive it till it dies and then decide. Just my

Oil pan is no big deal. Pull the engine with the diff, shaft and disco attached and remove them after.

 

[C-ya]

Yeah, just pre-failure replacement so I can depend on it to go to the east or west coast or anywhere in between if I need to. I'll drive it awhile longer no doubt, as I don't want to contemplate replacing it myself in the winter.

 

[Mooseman]

It might be cheaper to get it rebuilt locally because I think online rebuilders are using the fact of the rarity of the LH6 for the pricing. I saw a $1000 difference wth a truck engine. And you can have non-DOD parts installed which are cheaper. Otherwise it's just a regular LS rebuild.

 

[mrrsm]

And if you want to "Warm Up" to the idea of doing this yourself and sort of get in the mood when things actually DO warm up again where you are... Eric "O" from South Main Auto performs a 5.3L Engine Swap in a Multi-Part Series that has Quite a Few Tips. Even though the 'patient' he operates on in these One Hour Videos is a GM Truck... this series is still well worth watching:

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[C-ya]

@Mooseman I hear ya on the rebuild. I would love to rebuild it without the DOD items. I built the SBC that I put in my Isuzu Hombre but I had access to a shop with a lift and all the special tools. I'll check with the shop I use for work I don't do myself and see what they say. Jasper has a non-DOD engine for the vehicles that came with them originally but they are more expensive on the LH6 so I imagine they would charge more the the non-DOD but it is worth a call or email.

@MRRSM I like Eric O.'s videos. He helped me repair the electro-viscous clutch in the wife's Sportage. Same exact problem his customer had, so I did the same repair. I'll check his videos out. I like watching him as I like his style and common-sense approach.

 

[TollKeeper]

I have to ask what makes you think there is an issue going on with your current LH6? I have been having the same mentality on my Envoy V8 for 12 years and 100k miles. But she starts every day, and just keeps going.

 

[C-ya]

@TollKeeper I hate to be blindsided, so I would rather replace the engine - or at least have a plan ready to execute - should the current power plant go south. The thread about why you like the TB and how you use it got me to thinking that it really is perfect for me. Well, if she got better fuel mileage, but I can overlook that. I just don't want to get 800 miles from home on a trip and something catastrophic happens to the engine. No guarantees on anything, I know, but I like to play the safe game most of the time.

What is your engine doing? The smoke is getting more prevalent and more in volume when it does show up, so to me, that means things are getting worse. If that is a characteristic, then I guess I'm OK.

 

[TollKeeper]

Mine is just Valvetrain noise and piston slap, both are very common for the LS engines. And the noise is completely gone after about 5 mins of engine running, but its always nerve racking.

But I would ask you to think about it from a different angle. I get that you are just trying to be proactive about the engine. But these LS engines are so common, and so easy to be had.. Even if you did blow a rod 900 miles into a trip, you could easily find any shop (I mean everyone works on LS engines), and have them do the job. But you could be throwing out an engine thats going to last you another 70+++ miles, or it could blow up tomorrow. The best option for you is to probably get an engine leak down/compression check, and get the health of the engine. If you have wide varying numbers, or even a loss of compression on one cylinder, then I could see you going down the road you are on. The smoke could be a stuck ring, or it could be excessive wear on the cylinder bore. I had a car that had 2 stuck rings, and oil sweep ring. I drove that car for another 70k miles, then I wrecked it. I drove it to the junk yard, and went on my merry way.

I have been having the same thought process on my truck to be honest, I want to drop in a 6.0, and maybe supercharge it, and have some fun with it. But as long as this 5.3 keeps rocking away, I cant justify throwing it out, just because. I drive this truck as hard today, as I did when I bought it 103k miles ago. And she just keeps going.

 

[C-ya]

Good idea on compression and leak down testing. I'll do that before I go any further.

 

[Reprise]

Coming in late here, but I agree with the others. If the engine still has good compression, etc., the last thing to do would be an engine oil analysis at your next oil change. I know you maintained the oil, changing it at NLT 20%, so you'll probably be just fine. The report you get will also give you an idea of how long you have, if it does find excessive wear.

If it comes back with low wear metals on the bearings & rings, the only thing I'd do with that motor is fix the leaks you mentioned in your 'for sale' post. I would not crack it open except to replace seals / gaskets, etc. Good compression should equal another 50K miles (or more), the way you're taking care of it. Just keep up w/ the oil level, as needed.

You can use that time to find another LS and rebuild it, if you're itching for another project and the peace of mind that a new motor would bring / match it up w/ the newer trans.
It will cost $$$$ for that peace of mind, of course.

That new motor doesn't have to be a LH6, either. Any Gen-III / non-DOD 5.3 would be a great choice (your '05 should have a 24x reluctor; I'd try and stick with that, if possible.) You might give up the aluminum block you have now, but you'd only gain about 200lb in weight, you'd have a stronger block (e.g.; if you wanted to go wild and build for boost down the line), and you could make a lot of coin back selling the old block, especially if the rings didn't gouge any of the cylinders.

If you're seeing the smoke mostly at (cold) startup, and not seeing it once at op temp, you'll again have time before you have to address it. You'll also see oil consumption increase as it gets worse, but at the rate you're describing, I think you're leaking more than your burning, right now -- especially if you haven't seen increased consumption rate in awhile. Fixing the leaks will also help determine where the oil's going, of course.

Bottom line -- if it's running well now, and you're not having to put a ton of new $ into the driveline, it should continue to run well for awhile longer. I *would* prepare to do the water pump before too long. It's not a terrible job (the fan clutch nut is probably the worst part of it). Do the t-stat, hoses & belts while you're in there, one or both tensioners if you need them, and you should be fine to go wherever you want. (there are two WP types; the older ones have an integrated neck / housing with the t-stat inside (non-servicable; sold as a unit.)

I went from IL to NW Montana & back with 5000lbs on the back of the Envoy two summers ago, sometimes driving 12hr days up mountains during +95F temps. Except for the t-stat bolts working themselves loose, which I tracked down / fixed when I got back (I checked oil / coolant daily and added as needed), I didn't have any break / fix issues during that trip (about 3000 miles, total, with climbs up to 6000-8000ft). Yeah, the coolant / trans temps got elevated a couple of times, but I monitored them and adjusted accordingly. Never overheated or broke down.

10,000 miles / 18mos later, I still don't have any driveline issues (156K on the engine now; trans was rebuilt before that trip). If I needed to go anywhere in the country with it, I wouldn't hesitate to get in and go, with confidence (although I don't use it for towing a travel trailer any longer)