Getting my Chevy 4.3 to 300k

Messages
2,337
Location
South Carolina
As an owner of old vehicles, obsessing about oil is the least of your worries. Keeping up with all the other ageing parts will keep you busy. Any PCMO 10w-30 (synthetic/conventional/HM) will work fine. If your having blow by, stay with a HM oil. Stay away from diesel oil and after market additives.
 
Messages
1,122
Location
Pa, USA
Originally Posted by Superbuick96
Aint that the truth! I owned a 2003 Blazer for 11 years, the thing nickle and dimed me the entire time. Although living in the Rustbelt doesn't help either. The 4.3 was solid though the previous owner drove 28k on a oil change, the engine didn't cause me any problems other than a head gasket. I used Vavoline Max life full syn, Vavoline Max Life simi-syn, VWB, PP, Mobil1. My friend who is a mechanic drives it now he's approaching 200k.
Hey, how is that. We hold much in common here. We both owned a 2003 Chevy Blazer for you know what? 11 years. I got mine at around 32,600 miles in 2006. They told me it was a leased vehicle in New Jersey. I knew who the leasing dealer was, but didn't know actually leased it. I once called them for the service records and they told me they didn't have any, other than a fuel cap(which they replaced with a piece of junk). So I didn't know if the leasers did the oil changes somewhere else or never. But I didn't do a head gasket like you did. But I had to do the lower manifold gasket before 100,000 miles. I always called my relationship with the Blazer a love/hate one. I loved the solid feel of it, but I thought it caused more problems than necessary. I had to replace O2 sensors at around 42,000 miles. I got married owning it, in 2009 and wife brought a 2004 Ford Sport Trac, she actually bought new. Since the vehicles were relatively new and paid for back them, we decided to try to put more miles on the Blazer than the Sport Trac as that one would be replaced first. I went through a time I didn't have to do much to the Blazer, but seemed short lived. It seemed I always had to do something about every 6 months. Once my wife said, you aren't doing anything to the Sport Trac. I told her because I didn't have to(meaning nothing wrong to fix). 2017 showed up and got the blazer to 133,000 miles, which was our targeted goal to replace it. And just like me, according to the vehicles in your signatures, you didn't get another Chevy. My Blazer replaced a 93 S-10. I thought 10 years, GM would have learned to make a more reliable vehicle. Wrong. So I thought I will try a Toyota.
 

CharlotteB

Thread starter
Messages
16
Location
North Texas
Wow, sounds like a lot of y'all on here have had experiences with GMT325 vehicles. It's nice to hear good things about long life.
Originally Posted by NH73
Like everyone says, "Its a good tough engine." But everything else goes wrong with the vehicle.
Quite accurate! The interiors especially love to fall apart laugh. But I'm fine with some duct tape here and there. I keep vehicles based on the powertrain and chassis, and I've had few complaints there (It might even still be on the original clutch). I do stay on top of maintenance. Lots of grease every time I do an oil change. I also recently replaced the plugs, wires, and rotor and cap. Thankfully I don't have to worry about rust around here, and the only accessory I've ever had go bad is the alternator.
Originally Posted by 14Accent
If you want to keep it for the long haul, and the intake has never been off, then you should seriously consider replacing the lower intake gaskets and replacing the fuel injection with the MPFI version. You'll have the peace of mind knowing you have new gaskets, and the benefit of brand new (and much improved) fuel injectors.
Is it possible to swap the spider injectors with poppet valves for multiport? How hard is it to get the intake manifold off? It's not that I am afraid to do anything to it (I recently had the whole top end off my Dodge Charger) but I'm wondering if it'd be a better idea to just wait until something does go wrong and then do a complete rebuild, since I have no intention of ever getting rid of this truck. That's why I was asking about oil; to keep it healthy as long as possible.
 
Messages
184
Location
virginia
Oil is the least of your concerns getting to 300k. I use full synthetic (factory spec'd 5w30) and change it every 5k miles. At 280k miles now. That's my oil formula for long life (I have a 99' ohv 4.0L Ford. Since I bought it used I put 30-35k miles a year on it). IMO not trying to do extended drains is the only oil variable that matters. I don't care how good an oil is at neutralizing and containing byproducts of combustion, it's still circulating in your crankcase (and I've lived long enough to see the practices of the few people who keep their cars 300-400k miles. They don't do 10k mile oil changes). Oil is not what keeps a truck on the road to 300k miles. Changing upper and lower ball joints, inner/outer tie rods, shocks, sway bar links, diff and transfer case fluids, spark plugs and coil packs plus other things likely not make it to 300k miles: water pump, wheel bearings, alternator, starter, sensors, EGT valves etc. Its the accumulation of and things that take a car/truck off the road. Everything listed I change myself and it's cheap. If I had to pay somebody for everything I've done in the last 80k miles it might be off the road. The good thing is once the main wear items are replaced (ball joints, bushings etc). It will be another 100-200k miles before they need it again. Also WASH the vehicle regularly. Nothing worse than mechanics being good but succumbing to rust. Also move South if you aren't already there lol.
 
Messages
1,122
Location
Pa, USA
Originally Posted by yaris0128
Yep just keep doing what your doing and stick to your scheduled maintenance
This I agree to. Valvoline Maxlife is good product. I was using that in my last oil change on my Blazer. I actually used the full synthetic Maxlife, but it actually leaked more with that than the regular Maxlife. My oil cooler lines were leaking and I offloaded before they got worse.
 
Messages
115
Location
Levittown, PA
I'll echo what everyone else said, stick to what you're doing but change those intake gaskets before they come to bite you. And when it hits 300K, send that thing up north and I'll buy it!
 
Messages
1,623
Location
MN
Originally Posted by 14Accent
If you want to keep it for the long haul, and the intake has never been off, then you should seriously consider replacing the lower intake gaskets and replacing the fuel injection with the MPFI version. You'll have the peace of mind knowing you have new gaskets, and the benefit of brand new (and much improved) fuel injectors.
Is it possible to swap the spider injectors with poppet valves for multiport? How hard is it to get the intake manifold off? It's not that I am afraid to do anything to it (I recently had the whole top end off my Dodge Charger) but I'm wondering if it'd be a better idea to just wait until something does go wrong and then do a complete rebuild, since I have no intention of ever getting rid of this truck. That's why I was asking about oil; to keep it healthy as long as possible.[/quote] The job couldn't be easier. I'm sure there's plenty of YouTube videos to help with any questions. The injector assembly I mentioned does convert from poppet injectors to electronic injectors. It's a direct bolt in swap, and it's well worth the money. Those poppet injectors were a terrible idea.
 
Messages
768
Location
Alaska and Wisconsin
Thanks for the quick replies! I do change the coolant more frequently than called for. Don't want to risk anything with it. I recently changed the clutch fluid, brake fluid, PS fluid, and MTF too. Is 5,000 miles a good OCI for Maxlife in my application? It sounds like Maxlife meets with approval around here.
Should be okay. Had a 1993 Olds AWD Bravada with a 4.3L "W" code engine that I took to 278,000 miles before selling her a few years ago. It was my Alaskan Snow-Go. The drive train was all original; I just changed gear and trans fluids on-time with synthetics. The motor oil was mostly Valvoline Durablend every 3000 to 3500 miles. Surprisingly, I never changed a wheel bearing. Tires, brakes, rotors, steering, suspension and injector components... sure. They were typical wear components.

The 1993 period full-time AWD system in the Bravada and Astro Vans were the bomb! Ours was fantastic and never gave an ounce of trouble. And it must have been efficient, as the truck always returned a respectable 18 to 21 mpg in mixed to mostly highway driving.

Get this... it was NEVER garaged in Alaska. It always started, even down to -30 and -35 degs F in the greater Anchorage area. The drive train was fantastic. The interior seating was fantastic. When everything else started to fail around the drive train, I decided it was time to sell the baby. Miss her today!

Mine looked just like this one:

1993 Olds Bravada.JPG
 
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Messages
1,346
Location
PEARL River la
I kept up a customer vehicle 2001 S10 with standard. Things I changed were distributor, transmission at 300k+, and retorqued differential yolk. He sold it at 500k all original except repairs I listed. Changed oil at 5k with Valvoline 5w30.
 
Messages
164
Location
California, United States
Hey y'all, I have a 2001 Chevy S10 with the 4.3 V6 that just hit 200k miles. I love this truck. And it's a manual! My goal is to reach 300k miles without any major repairs, and I'd like advice on engine oil. A bit of background- I do keep on top of maintenance, but I also use it like a truck. I haul around welders and riding mowers, drive on dirt roads, and occasionally I end up towing over 6,000 pounds. What I've been using is Valvoline Maxlife 10W30 semi-synthetic with a WIX filter, changed every 5,000-6,000 miles. I don't know if I should stick with this or try something fancier. What are good options? I'm just trying to do the best for my engine, so all input is appreciated. Some of the options I considered- Sticking with 10W30 Maxlife Pennzoil Ultra Platinum 10W30 Schaeffers SynShield 10W30 or 15W40 diesel oil Rotella T5 10W30 or 15W40 diesel oil Is thicker oil a bad idea? Is diesel oil a good thing in a 4.3? Should I be leery of stretching my OCI? As a side note, I do have a few small leaks and a tiny bit a of blow-by, which the Maxlife helps with. If I go with a non high-mileage oil and it starts to leak more I'll add some STP stop-leak to it, which has worked great for me in the past.
If you want you could use the valvoline 10w30 full syn if you want but honestly if its been going this long without any other oil I would probably keep it like that and do a few oil samples say 2 or 3 for your next few oci to see how its going. The filter is good, wix is usually quality stuff for the most part.
 
Messages
4,632
Location
Decatur AL USA
Hey y'all, I have a 2001 Chevy S10 with the 4.3 V6 that just hit 200k miles. I love this truck. And it's a manual! My goal is to reach 300k miles without any major repairs, and I'd like advice on engine oil. A bit of background- I do keep on top of maintenance, but I also use it like a truck. I haul around welders and riding mowers, drive on dirt roads, and occasionally I end up towing over 6,000 pounds. What I've been using is Valvoline Maxlife 10W30 semi-synthetic with a WIX filter, changed every 5,000-6,000 miles. I don't know if I should stick with this or try something fancier. What are good options? I'm just trying to do the best for my engine, so all input is appreciated. Some of the options I considered- Sticking with 10W30 Maxlife Pennzoil Ultra Platinum 10W30 Schaeffers SynShield 10W30 or 15W40 diesel oil Rotella T5 10W30 or 15W40 diesel oil Is thicker oil a bad idea? Is diesel oil a good thing in a 4.3? Should I be leery of stretching my OCI? As a side note, I do have a few small leaks and a tiny bit a of blow-by, which the Maxlife helps with. If I go with a non high-mileage oil and it starts to leak more I'll add some STP stop-leak to it, which has worked great for me in the past.

My uncle's old S10 (now belongs to his mechanic) was approaching 500,000 mi last I heard and it had 10W-30 conventional for the first 200,000 mi and Rotella 15W-40 (It's in the deep south) since. That said I doubt it would have made a real difference if it had run exclusively on either oil. I think many times oil brand and grade changes do more for the owner than the vehicle.
 
Messages
50
Location
Arizona
Hey y'all, I have a 2001 Chevy S10 with the 4.3 V6 that just hit 200k miles. I love this truck. And it's a manual! My goal is to reach 300k miles without any major repairs, and I'd like advice on engine oil. A bit of background- I do keep on top of maintenance, but I also use it like a truck. I haul around welders and riding mowers, drive on dirt roads, and occasionally I end up towing over 6,000 pounds. What I've been using is Valvoline Maxlife 10W30 semi-synthetic with a WIX filter, changed every 5,000-6,000 miles. I don't know if I should stick with this or try something fancier. What are good options? I'm just trying to do the best for my engine, so all input is appreciated. Some of the options I considered- Sticking with 10W30 Maxlife Pennzoil Ultra Platinum 10W30 Schaeffers SynShield 10W30 or 15W40 diesel oil Rotella T5 10W30 or 15W40 diesel oil Is thicker oil a bad idea? Is diesel oil a good thing in a 4.3? Should I be leery of stretching my OCI? As a side note, I do have a few small leaks and a tiny bit a of blow-by, which the Maxlife helps with. If I go with a non high-mileage oil and it starts to leak more I'll add some STP stop-leak to it, which has worked great for me in the past.
Had a 1994 Silverado 4.3 V6 319,000 when trans. went out for the second time. Engine still ran great. Air went out, Trans went out and tires shot. Wife said no more, time for new vehicle. Broke my heart. I was original owner.
 
Messages
6,887
Location
Roanoke Virginia
Nice. Don’t have any Chevrolet currently but we have almost 280,000 on our 2004 Camry if that counts. It’s our highest mileage car besides my dads Freightliner which has over 1 million miles on it it’s a 2000 model.
 
Messages
324
Location
Iowa
Hey y'all, I have a 2001 Chevy S10 with the 4.3 V6 that just hit 200k miles. I love this truck. And it's a manual! My goal is to reach 300k miles without any major repairs, and I'd like advice on engine oil. A bit of background- I do keep on top of maintenance, but I also use it like a truck. I haul around welders and riding mowers, drive on dirt roads, and occasionally I end up towing over 6,000 pounds. What I've been using is Valvoline Maxlife 10W30 semi-synthetic with a WIX filter, changed every 5,000-6,000 miles. I don't know if I should stick with this or try something fancier. What are good options? I'm just trying to do the best for my engine, so all input is appreciated. Some of the options I considered- Sticking with 10W30 Maxlife Pennzoil Ultra Platinum 10W30 Schaeffers SynShield 10W30 or 15W40 diesel oil Rotella T5 10W30 or 15W40 diesel oil Is thicker oil a bad idea? Is diesel oil a good thing in a 4.3? Should I be leery of stretching my OCI? As a side note, I do have a few small leaks and a tiny bit a of blow-by, which the Maxlife helps with. If I go with a non high-mileage oil and it starts to leak more I'll add some STP stop-leak to it, which has worked great for me in the past.

We had a 1991 GMC Jimmy with a 4.3L. It is the last GM product I will ever own, but it wasn't because of the motor. That thing was really solid. Ours had a remote oil filter in the left front fender and the adapter plates were known to leak (news to me at the time). I dang near ran it out of oil going to work one day. I had no idea it was leaking. I went to the store and put in over 2 quarts of oil to get it back to the add mark! The thing was almost bullet proof. I sold the truck with ~265K on it and it was still going strong.

I think a good maintenance schedule like you have is the best medicine. A change in oil at this point likely won't make a difference.

Just my $0.02
 
Messages
768
Location
Alaska and Wisconsin
We had a 1991 GMC Jimmy with a 4.3L. It is the last GM product I will ever own, but it wasn't because of the motor. That thing was really solid. Ours had a remote oil filter in the left front fender and the adapter plates were known to leak (news to me at the time). I dang near ran it out of oil going to work one day. I had no idea it was leaking. I went to the store and put in over 2 quarts of oil to get it back to the add mark! The thing was almost bullet proof. I sold the truck with ~265K on it and it was still going strong.

I think a good maintenance schedule like you have is the best medicine. A change in oil at this point likely won't make a difference.

Just my $0.02
Come to think of it, my 1993 Bravada had that same remote oil filter. I did have to replace one of the oil lines because of a leak (or was it the whole remote assembly with included lines, I don't remember). Though, the leak wasn't as bad as yours; it was only gradual as I remember. I considered that replacement as routine maintenance as it likely happened well after 100,000 miles.

Loved that Bravada!
 
Messages
24,260
Location
Dallas,Tx USA
Keep on keeping on!! Stick with your Maxlife 10W30. My gf's dad had an S10 Blazer of that same vintage. He either had near 300,000 or a little over 300,000 on his. He only sold it because he needed a bigger "truck" to haul around all his maintenance equipment and items for his rental properties. He is a Castrol guy and always used Syntec 10W30 in it.
 
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