trailblazer 4.2 oil?

Joined
Dec 12, 2006
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10
Location
lousiana
I did a search and didnt find much on this engine. I have 85000 miles on it and was wondering if anyone had some oil recommendations on this. Thinking of switching to synthetic but just wanted some opinion. Thanks.
 
Joined
Jun 21, 2002
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CarMax
What are you running now? What's the OCI? Any UOA's to share? Why switch, is something not working properly?
 
Joined
Aug 21, 2008
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ON, Canada eh?
 Originally Posted By: daves87rs
Any synthetic should be fine.
+1 \:\! Use the cheapest SM / ILSAC-GF3/4 oil you can find...
 

daviddsims1

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Joined
Dec 12, 2006
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Location
lousiana
I bought the truck with about 75000 miles on it. I went by the OLM and it has 7500 miles on this oil change with shell dino oil. It still has 15 percent left on it. Was just gonna change it myself for the same price with synthetic as dino at the Shell Rapid Lube place.
 
Joined
Nov 29, 2007
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Happy Valley, PA
My current 4.2L (Envoy) has PP 5w30 since dumping the FF at 1500mi. 6000 now. and will get QHP next. Use any typical syn. and change it when the OLM says to and you will be fine.
 

daviddsims1

Thread starter
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Dec 12, 2006
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lousiana
Why are you switching to QHP gmctodd? I thought PP was better than QHP? I havent kept up with the oils lately.
 
Joined
May 15, 2008
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New York
I've used nothing but Mobil 1 5W-30 in my Trailblazer since dumping the factory fill. It began consuming two quarts of oil every 5000 miles around the 75000 mile mark. I switched to Valvoline Maxlife Synthetic Blend at 94000 and it's been in for 2000 miles with zero consumption. If I can get it to the 5000 mark burning less than a quart I will stick with the Maxlife.
 
Joined
Sep 23, 2007
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Florida
 Originally Posted By: daviddsims1
Why are you switching to QHP gmctodd? I thought PP was better than QHP? I havent kept up with the oils lately.
PP might be better than QHP, but many stores have been clearing out QHP and Q-torque at bargain prices. Since QHP and Q-Torque are still high quality oils, it makes sense to use them in a Trailblazer engine.
 
Joined
Feb 23, 2009
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Michigan
 Originally Posted By: artificialist
 Originally Posted By: daviddsims1
Why are you switching to QHP gmctodd? I thought PP was better than QHP? I havent kept up with the oils lately.
PP might be better than QHP, but many stores have been clearing out QHP and Q-torque at bargain prices. Since QHP and Q-Torque are still high quality oils, it makes sense to use them in a Trailblazer engine.
 
Joined
Oct 1, 2009
Messages
1
Location
Rocky Mountains
Resurrecting an old thread... My '02 Olds Bravada with the 4.2 just turned over 105k... about 5k miles ago the motor just starting sounding noisier and noisier. I've used M1 since new, changing every 3k-5k miles. I've heard that M1 isn't the oil it used to be so switched to Valvoline synthetic....the engine continued to be noisy (the car lives in a climate-controlled garage), especially during startup getting quieter with higher temps - my thought was maybe piston slap. As an experiment I bought a bottle ZDDPlus and poured it in right after my last oil change, while the engine was running. Long story short, ALL of the noise disappeared and the engine now sounds almost new again and has continued for 2k miles now. ZDDPlus doesn't make any claims that relate to my situation, but it sure worked.... does anyone have any input on possible cause /effect? TIA.
 
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