hello,i just bought a 2011 sierra told dealer i wanted a 5.3 with 342 rears,when he calls me that the truck is in,when i looked at the window sticker it had the afm iron block i really had done no research on afm but i really liked the truck so i didnt reject the truck because of the afm.after i got home i looked up the reviews of the afm engines it seems what i have read no one likes the motor and it supposed to use oil within 30000 miles,i hope someone here can tell me if this is a good engine or not i really like truck and just hope i have not bought trouble thanks and i am a new to this forum all advice is appreciated
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5.3 afm
- Thread starter ewrob
- Start date
happy 2011
New member
ok AFM is only Active Fuel Management.
It's the same motor (5.3) but saves gas on the highway. What it does is shut fuel off to cylinders while driving at steady speeds when the engine does not need the power of all 8 cylinders. This equeals fuel savings.
So you got what you wanted a 5.3 be happy. But what i will want to know is if your check engine light comes on with a code of 521. ant time soon Nothing to worry about.
It's the same motor (5.3) but saves gas on the highway. What it does is shut fuel off to cylinders while driving at steady speeds when the engine does not need the power of all 8 cylinders. This equeals fuel savings.
So you got what you wanted a 5.3 be happy. But what i will want to know is if your check engine light comes on with a code of 521. ant time soon Nothing to worry about.
All 5.3 engines come with Active Fuel Management (AFM) which disables 4 cylinders when conditions are right to conserve fuel. This has allowed them to advertise higher fuel economy ratings. Weather is saves anything is yet to be substantiated. From my personal opinion, it saves very little. I have driven AFM 5.3L engine since 2008 and on average it is the very same mileage I got with my 2004 GMC, same engine and everything else same on truck except color.
As for problems. Yes some engines have oil issues but those are usually engines from 2007, 2008 models. These modern engines put a lot of stress on engine oil. Oil is the life blood of your engine so you need to be sure what you are using is the best you can get, not what is the cheapest or is the most hyped. Do not cut corners when it comes to engine oil and filters as many vehicle owners tend to do.
My advice, use a 100% synthetic motor oil and do not let the price dictate the oil you will use. Remember, you get what you pay for.
As for problems. Yes some engines have oil issues but those are usually engines from 2007, 2008 models. These modern engines put a lot of stress on engine oil. Oil is the life blood of your engine so you need to be sure what you are using is the best you can get, not what is the cheapest or is the most hyped. Do not cut corners when it comes to engine oil and filters as many vehicle owners tend to do.
My advice, use a 100% synthetic motor oil and do not let the price dictate the oil you will use. Remember, you get what you pay for.
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5.3 afm concerns
thanks for your advice,i had allways liked the 5.3 engine the last new chevy i bought was in 2006 and it did not have the afm in it i did not realize when i asked for the 5.3 they all came with fuel management on them.i guess sometimes the internet can confuse you when it comes to reviews of something,most of what you read are the owners who have had problems with their vehichle i hope mine turns out to be trouble free,i have been driving a f150 the past couple years,not a bad truck but the ride of the sierra is way better than the f150,i plan on using synthetic oil which one do you recomend to use,i know on the oil cap it just recomends 5w30 which i had been using in all my vehichles,but i am going to use synthetic in this one.thanks
thanks for your advice,i had allways liked the 5.3 engine the last new chevy i bought was in 2006 and it did not have the afm in it i did not realize when i asked for the 5.3 they all came with fuel management on them.i guess sometimes the internet can confuse you when it comes to reviews of something,most of what you read are the owners who have had problems with their vehichle i hope mine turns out to be trouble free,i have been driving a f150 the past couple years,not a bad truck but the ride of the sierra is way better than the f150,i plan on using synthetic oil which one do you recomend to use,i know on the oil cap it just recomends 5w30 which i had been using in all my vehichles,but i am going to use synthetic in this one.thanks
I have always used Synthetic in my GM vehicles dating back to 1975 and I have NEVER once had any engine related problems. I can't recall the last time I checked oil on one of my GM vehicles and it was low.
Currently run synthetic oil in my 2010 GMC Sierra SLT Extended Cab Z71 All Terrain and in my 2009 Cadillac CTS4 Performance sedan which requires synthetic oil (came factory filled with synthetic oil).
This is the Oil I would recommend.
Currently run synthetic oil in my 2010 GMC Sierra SLT Extended Cab Z71 All Terrain and in my 2009 Cadillac CTS4 Performance sedan which requires synthetic oil (came factory filled with synthetic oil).
This is the Oil I would recommend.
I change oil once a year or 15,000 miles on both the truck and the car. The truck sees more miles than the car because I only run the car in the summer months and store it in the winter, so about 7,500 is all it gets per year. PS-Never have I had to add a drop of oil to a GM engine in over 25 yrs.
When the truck is new, I switch out the OEM oil at about 1,000 miles (+/-) and install synthetic oil in every hole. Both my truck and car are 100% synthetic lubed, engine, trans, both axles and PS. Firm believer in synthetic oils for over 20 yrs.
Lots of people think synthetic oil is a waste but these modern engines need synthetic oil to survive. These engines run hotter, are more fuel efficient with the cylinders shut down to save fuel, they need a top oil to protect them. Oil is not just oil. There is a difference in high-performance oils and the oils that just meet the minimum industry requirements. Oils in the marketplace only have to meet minimum performance levels set by API, they are not required to exceed them.
All major synthetic brands are not the same; you can expect formulations to differ from one to another and very few will stand behind their products and tell you how long they are good for. Only 2 companies I know of that do, Mobil 1 Extended performance and AMSOIL Synthetics will guarantee their oils for specific miles.
Mike
2010 GMC Sierra E. Cab SLT Z71 All Terrain 5.3L
2009 Cadillac CTS4 AWD Performance Sedan 3.6L
When the truck is new, I switch out the OEM oil at about 1,000 miles (+/-) and install synthetic oil in every hole. Both my truck and car are 100% synthetic lubed, engine, trans, both axles and PS. Firm believer in synthetic oils for over 20 yrs.
Lots of people think synthetic oil is a waste but these modern engines need synthetic oil to survive. These engines run hotter, are more fuel efficient with the cylinders shut down to save fuel, they need a top oil to protect them. Oil is not just oil. There is a difference in high-performance oils and the oils that just meet the minimum industry requirements. Oils in the marketplace only have to meet minimum performance levels set by API, they are not required to exceed them.
All major synthetic brands are not the same; you can expect formulations to differ from one to another and very few will stand behind their products and tell you how long they are good for. Only 2 companies I know of that do, Mobil 1 Extended performance and AMSOIL Synthetics will guarantee their oils for specific miles.
Mike
2010 GMC Sierra E. Cab SLT Z71 All Terrain 5.3L
2009 Cadillac CTS4 AWD Performance Sedan 3.6L