[71GP76TA]

Yesterday the new truck I ordered finally came in yesterday. Its a '25 GMC Sierra 1500 with a 6.2. I am well aware of the lifter problems. Got to thinking and wondering if a zinc additive might be beneficial to the cam and lifters. Yes... I am aware that the cam and lifters are roller and shouldn't need the zinc...... but....

[michaelfind]

I would be concerned that it might damage your emissions control systems and then you will have a difficult time passing the "smog tests" I have heard are required in California. But I'm no expert on this, so maybe others will answer soon.

[camerjeff]

With the Spat of recent connecting rod failures ( or Bearings ) on the Gen 5 Truck 6.2 engines, I would not add anything to the oil that is not called out for by GM, and I would either have all the oil changes done on schedule by a GM dealer while the warranty period is in effect. I have heard that it is effecting only the 6.2 truck engines built in the St Catherines Ont. & Springhill TN. plants. I suspect it will end up being a supplier issue with the bearings, as the issue has not been seen in the 5.3 or 6.6 truck engines, or the 6.2 Corvette engines that all use a different bearing material, if not a different supplier.

Just a word of caution as I don't think the issue has really gone mainstream yet, even though the NHTSA has opend and investigation about it.

https://gmauthority.com/blog/2025/01...gine-failures/

[tom s]

Change oil every 3000 is the best thing GM has told me.FWIW,tom

[The Champ]

For warranty purposes, only Dexos certified oil should be used.

I'm not aware of any high ZDDP level oils that come in the correct 0W20 weight.

And then there is the problem with the emissions systems...

[KS circutguy]

Cats hate zinc.

[muscle_collector]

for warranty issues you are way better off to let the dealer do all the service on vehicles. if push comes to shove they will make you absolutely prove you had it serviced on schedule and used the proper oil and filter. if you cant prove it, bam you have a voided warranty. i never change my oil on any of my driver vehicles anymore. i did the math on a couple of my older ford 6.7 diesels and it was going to cost me more in oil and filter than the ford dealer charges to do it.

[ponchjoe]

Just good maintenance. As others have said 3k oil changes using GM spec oil and a good filter. No ZDDP or any additive especially under warranty

[71GP76TA]

Originally Posted by tom s

Change oil every 3000 is the best thing GM has told me.FWIW,tom

I was planning on every 5,000. Thats what I did on my 2018 Sierra(6.2) and do on my '21 Challenger.

[71GP76TA]

Originally Posted by KS circutguy

Cats hate zinc.

Thats what I heard.

[71GP76TA]

Originally Posted by camerjeff

With the Spat of recent connecting rod failures ( or Bearings ) on the Gen 5 Truck 6.2 engines, I would not add anything to the oil that is not called out for by GM, and I would either have all the oil changes done on schedule by a GM dealer while the warranty period is in effect. I have heard that it is effecting only the 6.2 truck engines built in the St Catherines Ont. & Springhill TN. plants. I suspect it will end up being a supplier issue with the bearings, as the issue has not been seen in the 5.3 or 6.6 truck engines, or the 6.2 Corvette engines that all use a different bearing material, if not a different supplier.

Just a word of caution as I don't think the issue has really gone mainstream yet, even though the NHTSA has opend and investigation about it.

https://gmauthority.com/blog/2025/01...gine-failures/

This truck was built at the FT Wayne plant.

[GtoFM]

Originally Posted by muscle_collector

for warranty issues you are way better off to let the dealer do all the service on vehicles. if push comes to shove they will make you absolutely prove you had it serviced on schedule and used the proper oil and filter. if you cant prove it, bam you have a voided warranty. i never change my oil on any of my driver vehicles anymore. i did the math on a couple of my older ford 6.7 diesels and it was going to cost me more in oil and filter than the ford dealer charges to do it.

Years ago, an auto mechanic friend told me, almost word for word, what muscle collector said. With all the internal hyd, goings on, a little dirt will screw up a lot of things. Without proof of recommended maintenance, good luck on warranty claims. Your call.

[jhein]

For a vehicle that's under factory warranty, I wouldn't go anywhere but a dealer and I'd follow whatever intervals and products the manufacturer recommends. Then if it fails, it's on them, maybe.

[camerjeff]

Originally Posted by 71GP76TA

This truck was built at the FT Wayne plant.

Yes but the engine was most likely assembled in either St Catherines or Springhill, when I was at the Tonawanda Engine plant that also makes the Gen V v8 engines they told me they stopped making the 6.2 truck engine last fall.

Sorry for any confusion I may have caused, I was not speaking of the plant the truck was assembled at, just the engine.

[mgarblik]

High ZZDP oil in new roller valve gear engines really offers no benefits. I would recommend the proper DEXOS oil spec. for that engine. No additives. A zinc additive, over time will damage the converter (s) . It would take many thousands of miles but eventually you would begin seeing catalyst efficiency codes come up as the active material in the converters is degraded by the zinc. I would also recommend changing your oil at the 50% oil life remaining point on the driver information center. This averages 4500-5000 miles on most vehicles. We joke that changing oil when you get to 0-5% oil life remaining is for lease cars! Changing the oil and filter at 50% oil life is for people who own and plan to keep their vehicles! There is allot of truth to that though. Enjoy your new truck.

[Jay S]

I would disable the AFM/DFM. Those systems have created a lot of trouble and hardly help milage. With the harmful effects those systems do to the engine, the positives are not worth it.

[Sirrotica]

I've worked at too many GM dealers over my career to know that they strive to find a way to deny warranty claims. Don't give them any outs to deny a claim, especially at this point where GM is still not fessing up that there has been a problem with the newest 6.2 engines. Use the oil they recommend, change it before they recommend it, and have all the receipts to back up your claims. GM can be real bastards with warranty claims.

When I bought my 05 GTO they tried to weasel out of repairing the front suspension on my car with only 17,000 miles on it, I was so PO ed at the time I was ready to sell the car. Fortunately I was able to contact someone in GM warranty by phone that listened to my story, and got the problem taken care of, plus they extended the warranty on the suspension and steering to 5 years 60,000 miles for free over the factory 3 years 36,000 miles for my inconvenience. It sometimes takes persistence to get GM to honor warranty, but it's usually worth the fight.

I've seen many GM customers eat the bills because GM denied their claims for some minor detail. You can go above and beyond the first denial, but many people just give up. GM knows this, and if they think they can justify weaseling out, they'll try it. The car business is as corrupt as the government is, believe me.

Right now they're in bad financial shape due to their EV blunders, so the last thing they want is a huge engine recall to further empty their coffers.

[71GP76TA]

I have one of these coming. Its plug and play.

https://www.rangetechnology.com/blog..._s_dfm_module/

There is a button on the dash to disable the start/stop. Every time I shut it off it defaults back which is annoying. Hopefully the module doesn't interfere with anything. If it does I'll just simply remove it. My 2018 Sierra I have one plugged into the obd2 port that turned off the AFM.

I know the people at the dealership pretty well as I buy wholesale vehicles from them on a regular basis. If a warranty issue does come up.. I don't think there will be any problems unless the factory says otherwise.

I'll probably do the 1st oil change at around 1,000 miles. We are taking a little road trip this weekend with it

[Mr_GTO]

Originally Posted by tom s

Change oil every 3000 is the best thing GM has told me.FWIW,tom

This. Use good oil. Amsoil, Pennzoil Platinum AND KEEP IT CHANGED. Ignore the "Oil Life Monitor". Just keep it changed. Don't add anything to it. Straight OIL.

[Mr_GTO]

Watch the 1st 2 videos.
https://www.youtube.com/@themotoroil...uery=additives