Burning oil

[Jillb]

 

[j91z28d1]

My oil pressure is low I believe but oil level is fine...starting to think I bought a lemon

I'm sorry.

what you're seeing is actually very common on this board for this generation. yours at almost 250k miles is considered high mileage for these. honestly about 150k they are ready for some fixer ups. easy to do it you're a diy mechanic, sadly, if not, a shop can run up a bill almost as high as you paid for the truck pretty quickly.

on the upside yours is still running and driving, another guy pushed his budget to get into one for his family, got a 3rd party pre inspection and all, said it was good. valve train ate itself in a few months and shop replaced the engine. it seemed like a rough spot financially.


so the good, with your high mileage, your transmission has probably already been rebuilt. they go about 150k if you don't fix some flaws before hand that require removing the tranny to do. your low oil pressure might be a tick low, but it's pretty common. caused by a lot of different things but good part is it's still above what gm calls minimum. I'd have to look it up but it's something like 6psi at 1000 rpm hot. so as long as it's not currently tapping, and the oil pressure pops up pretty quickly when you Rev it up. it's probably not going to leave you stranded right now. it should start tapping pretty loudly before it does that. I personally depending your climate, I'd go with a thicker oil, something like a 10w40. another user here has gone as high as 20w50 without any negative side effects, and he sends used oil samples out for testing. of course up north in a cold below zero winter, 10w40 would be better. but during a hot summer whatever makes it run better, use less oil is fine.


depending on how tight your budget is, at this point. maybe just keep oil in it and enjoy driving it. others might have a better idea than me, but I can't even guess how long it will last as is. maybe forever, maybe not. there's an old saying that sometimes rings true. a chevy will run badly longer than most cars will run. haha



there's good info in these 2 sticky threads that might get you up to speed on what to expect. and maybe plan for. the trend you'll find there is these trucks will last forever if you get them early and have the budget to keep up with maintenance and fix a few engineers flaws along the way, over all being much cheaper than buying a new car. but if you walk into them without knowing what you're getting into. it can be hard to get on top of.

Thinking of Buying a 07-14 NNBS Tahoe/Suburban? Look Here

Gentleman I have been put in charge of making a sticky with common questions asked on the forum. These include common problems (please provide fixes and pics), some of the common mods (provide pics, step by step instructions, etc.) i.e. not air ride but maybe leveling the rear or front. I am...

www.tahoeyukonforum.com

IMPORTANT: The Chronicles of Low Oil Pressure by 07burb

Warning: this is a LONG read but may hold valuable information for others experiencing this same issue. This is what I've experienced and what seemed to work for me. Things may be different for you. Let me start from the beginning....there's also an amendment at the end of this post ---In June...

www.tahoeyukonforum.com

oh, and that k&n is very dirty. in general unless you need that 5 extra hp at wide open throttle. we tend to run stock air boxes with good paper filters. they keep a lot of dirt out of the engine that a k&n doesn't. plus the mass air flow sensor is picky about how the air flows thru it and gm put a lot of effort into getting smooth airflow across that sensor. it's honestly not a huge deal, but in states with picky emissions testing, some have had to go back to stock airboxs to get emissions based fault codes to clear. if yours is a daily driver, you might ask someone with a stock one if they want to buy your k&n setup plus give you their stock one. might make a few $ and come out with a better running setup in the long run.


good luck with it. it looks nice in the pics.

 

[Jillb]

I'm sorry.

what you're seeing is actually very common on this board for this generation. yours at almost 250k miles is considered high mileage for these. honestly about 150k they are ready for some fixer ups. easy to do it you're a diy mechanic, sadly, if not, a shop can run up a bill almost as high as you paid for the truck pretty quickly.

on the upside yours is still running and driving, another guy pushed his budget to get into one for his family, got a 3rd party pre inspection and all, said it was good. valve train ate itself in a few months and shop replaced the engine. it seemed like a rough spot financially.


so the good, with your high mileage, your transmission has probably already been rebuilt. they go about 150k if you don't fix some flaws before hand that require removing the tranny to do. your low oil pressure might be a tick low, but it's pretty common. caused by a lot of different things but good part is it's still above what gm calls minimum. I'd have to look it up but it's something like 6psi at 1000 rpm hot. so as long as it's not currently tapping, and the oil pressure pops up pretty quickly when you Rev it up. it's probably not going to leave you stranded right now. it should start tapping pretty loudly before it does that. I personally depending your climate, I'd go with a thicker oil, something like a 10w40. another user here has gone as high as 20w50 without any negative side effects, and he sends used oil samples out for testing. of course up north in a cold below zero winter, 10w40 would be better. but during a hot summer whatever makes it run better, use less oil is fine.


depending on how tight your budget is, at this point. maybe just keep oil in it and enjoy driving it. others might have a better idea than me, but I can't even guess how long it will last as is. maybe forever, maybe not. there's an old saying that sometimes rings true. a chevy will run badly longer than most cars will run. haha



there's good info in these 2 sticky threads that might get you up to speed on what to expect. and maybe plan for. the trend you'll find there is these trucks will last forever if you get them early and have the budget to keep up with maintenance and fix a few engineers flaws along the way, over all being much cheaper than buying a new car. but if you walk into them without knowing what you're getting into. it can be hard to get on top of.

Thinking of Buying a 07-14 NNBS Tahoe/Suburban? Look Here

Gentleman I have been put in charge of making a sticky with common questions asked on the forum. These include common problems (please provide fixes and pics), some of the common mods (provide pics, step by step instructions, etc.) i.e. not air ride but maybe leveling the rear or front. I am...

www.tahoeyukonforum.com

IMPORTANT: The Chronicles of Low Oil Pressure by 07burb

Warning: this is a LONG read but may hold valuable information for others experiencing this same issue. This is what I've experienced and what seemed to work for me. Things may be different for you. Let me start from the beginning....there's also an amendment at the end of this post ---In June...

www.tahoeyukonforum.com

oh, and that k&n is very dirty. in general unless you need that 5 extra hp at wide open throttle. we tend to run stock air boxes with good paper filters. they keep a lot of dirt out of the engine that a k&n doesn't. plus the mass air flow sensor is picky about how the air flows thru it and gm put a lot of effort into getting smooth airflow across that sensor. it's honestly not a huge deal, but in states with picky emissions testing, some have had to go back to stock airboxs to get emissions based fault codes to clear. if yours is a daily driver, you might ask someone with a stock one if they want to buy your k&n setup plus give you their stock one. might make a few $ and come out with a better running setup in the long run.


good luck with it. it looks nice in the pics.

Very very helpful info! Thank you so much! I live in Southern Missouri, so about to head into a hot summer...thinking of going with a 10w40 and as you suggested go back to stock air filter and diagnosing the misfire...a tune up and oil change and air filter is about all I can do right now but in February of next year might as well drop a new motor in it when I will have the cash to do so! Thank you to all that has replied! What a great forum!

 

[NardDog]

Wow, looks great!

I tried to post attachments/photos but not sure where or what happened to them

Its seems like your oil pressure is good. The catalytic converter can be purchased thru Rock auto and the have a shop weld it up. Then have a shop or a friend look to see if there are any codes stored in the memory of the truck, maybe a O2 sensor bank code. Lastly, keep an eye on the oil consumption. If it gets ridiculous you may have to consider a repair otherwise get used to the idea of checking the oil more often and topping off when needed. Its another chore I know but it ls better than buying a new truck. I would say you have a truck that with proper maintenance will last you a long time!

 

[Jillb]

Wow, looks great!

Its seems like your oil pressure is good. Have a shop or a friend look to see if there are any codes stored in the memory of the truck, maybe a O2 sensor bank code. If there are no stored codes I would say you have a truck that with proper maintenance will last you a long time!

Will do thank you and thanks for the replies!

 

[strutaeng]

It's "only" misfiring on cylinder 5?! No body has mentioned op is obviously running it with a misfire?

Running it with a misfire will destroy the catalytic converters... that's problem #1. Fix the misfire ASAP.

Problem #2 is oil pressure? Maybe, IDK on that one. If you don't have the AFM, that's fine.

Problem #3 is it's burning oil? This can actually cause problem #1, but you need further diagnosis to determine this...

I wouldn't say you bought a lemon. Afterall, it's a 200k+ vehicle. Maybe you bought someone's problems? I can see that happening. But at 200k+, that's to be expected, no?

 

[houstontaylor]

I have a 2003 Chevy Tahoe and at 290,000 miles it suddenly started burning a lot of oil, like in your case. Until then it was not burning any significant amount of oil. I figured that something internal broke and rather than digging into the engine to have it fixed I had the engine replaced with a remanufactured one. I never did find out what caused that though.

 

[jwth]

pull the number 5 plug and take s look at it. if it has been burninh oil it might be just worn valve stem guide seal which would foul the plug. If the plug is clean it may have an injector not firing or clogged up, may run thru oil pushing a dead cylinder.
switching to a heavier weight oil might pick up th oil pressure but getting a mechanical guage reading would be the the way to go to get a true picture. Sometimes an oil pump pick up tube seal will give low pressure

 

[hagar]

Replace your drivers side valve cover with the dorman 264-969 as a start for the oil burning issue. Change your plugs and cylinder 5 will most likely be getting oil build up on it from the oil burning problem causing the misfire, then run penzoil 5w30 synthetic high mileage formula with a half bottle of Lucas synthetic oil stabilizer. That is the best formula I could come up with after trial and error for the typical oil burning problem on some of these engines. I did it this way to try and make the oil stickier so it doesn't spash around as much, and it has been taking engines that were burning a liter of oil per 800 kms (i am Canadian eh,) down to a liter of oil every 2000 to 2500 kms, wich is livable.

Then pull your oil pressure sensor and oil pressure screen, throw the screen in the garbage, put in a new sensor with no screen, and change your oil every 4 thousand miles.

Then turn off the dod system with a tune.

 

[jwth]

rotten egg smell is sometime caused by tje moxture being too lean. The cold air intake will chamge yhr moxture due to less restrictions and the engine tine might nerd to be modified for that