Going synthetic on 2004 z71 tahoe? Leaks and oil change computer

[Red Rider]

Hi. I am thinking of switching to synthetic engine oil on a 2004 z71 Tahoe with about 137,000 miles. It has been well taken care of and has no leaks at all.

I picked up some Costco synthetic oil but after someone mentioned that there is a possibility that it could start leaking, have been thinking twice.

Anyone did this around that mileage?

Also, synthetic allows you to run longer between oil changes. The Tahoe gives you notice that an oil change is required based on analyzing the oil quality (if I remember right). Does the computer somehow factor in synthetic, or I would assume the synthetic takes longer to degrade so the computer would allow it to run longer in the truck?

Thanks.

 

[drakon543]

i would buy something better than crap bulk store synthetic if your going to do synthetic. synthetic oils are not created equal you pay for what you get with anything and oil still falls in this category. im not sure how the oil minder works in your truck but it generally does not know the quality of the oil so it will probably still pop up at the same intervals. synthetic oil is much better than when it first came out and alot of those myths stem from the original synthetic oils. i switched to a synthetic blend on a 97 tahoe and i think the oil leaks actually got better not worse. i switched to full synthetic on my 2000 civic with 140k because they are known to have oiling issues so i figured a higher quality oil might help. no problems there either. i also switched to synthetic on a 91 camaro with no adverse effects but its also an older engine so the extended oil life should be ignored.

 

[79jasper]

It's a old wives tale that synthetic causes leaks.

Sent from my SM-N960U using Tapatalk

 

[Red Rider]

Costco is usually pretty good, not the same as Walmart. They have good buyers and look out for their clients. I have heard good things.

 

[RaiderRodney]

I made the switch on my Hoe when I got her with around 155k with no problems. I'm with drakon543 though, I'd recommend using a good quality synthetic like the Pennz Ultra Platinum or Amsoil. You can catch rebates on the Pennz from time to time and it's already reasonably priced at Wallyworld.

 

[Red Rider]

This is the description of this oil:

$25/10qts. Kirkland Signature™ Full Synthetic 5W-30 Motor Oil is formulated to reduce wear on critical parts and maximizes fuel economy. Our 100% synthetic formulation provides long-lasting engine protection and performance. For use in gasoline, flex-fuel or gasoline-electric hybrid vehicles requiring SAE 5W-30 API SN PLUS, SN, SL and ILSAC GF-5, GF-4 or previous standards. Approved for use in all GM gasoline engines requiring dexos1™ Gen 2 5W-30.

I think it should work fine. They don' tend to get cheap products.

Thanks for the responses. Very helpful. I would love to know more about the sensor that gives you notice (OLM SENSOR?).

 

[rgosart]

I switched to synthetic on my 05 Tahoe with 180k and something on the back of the motor has started leaking. I believe it to be the rear main, but I am not 100% sure. I am not blaming the synthetic oil for the leak, but it can find weak points.

I could be wrong about this, but I believe the OLM (oil life monitor) is algorithm not sensor based. It looks at operating conditions, heat cycles, mileage, etc to determine when the oil needs to be changed. I have never gone by the OLM in my truck. Oil has been changed every 5k miles since new. Always before the software recommended the change.

 

[new2yukon]

I would NEVER change my oil based on today's stupid software engineers.

I've read a lot on switching to synthetic and most say within maybe 50k miles but after that stick dyno oil and just change regularly and use good oil like castrol or something

 

[TheAutumnWind]

I run full synthetic in all my vehicles. Never had trouble. 20+ year old trucks will leak eventually. On my Esky I change whenever the DIC recommends it, the oil and filters I run are good for 10k, but I wouldnt ever go that long. I spend way less money and time (fumoto drain valves are great!) changing it myself with quality stuff than I would having oil can henrys or whatever put some dino junk in it.