2001 Chevy Suburban 8.1L Oil Consumption

Greetings all!

I recently purchased the suburban listed in the title of this post. It is a 2500. It seems to be comsuming oil and I need to know if I should be concerned. I recently purchased this suburban to tow our camper, mostly on flatlands, but would like to take it to the mountains at some point. I have been using it as my daily driver just to ‘get to know it’ and hopefully get any ‘bugs’ worked out before we actually take it camping. My test usage includes hauling a 6’4"x12’ tandem trailer full of firewood a couple times a month. The suburban has 120K miles on it. I check the oil regulary and it seems that when hauling firewood, I may need to add up to a quart every couple times I haul. There are no drips that I can find and no odd smoke coming out of the tailpipe and no oily buildup at the opening of the tailpipe.

Any thoughts or opinions are appreciated.



We need to know how much oil you burn over how many miles, preferably how many miles can you drive before you’re down 1 qt of oil?

There was a time when 454 Chevy’s with 120K miles were only a step or two away from the shredder…A quart every 800 miles is normal…So is using 20-50 oil…

I have owned the suburban for approximately 3000k miles. So far I have had to add 2 qts of oil. I do not know exactly how many miles before I’m down a quart.

So it is recommended to use 20W 50 oil in the 8.1? Previous owner was running 5w30 valvoline conventional oil every 3k. I was going to convert over to amsoil 0w30 full synthetic in a couple days.

That type of consumption is entirely normal for that engine in a Suburban 2500. I worked with a person who had one in a Caprice station wagon, and it consumed oil from day one, even in normal driving (not towing).

As others say, just live with it, go to 20W50 oil in the summer, and keep several quarts of oil with you on the road. This engine is quite happy with inexpensive oil bought at a supermarket. Compared to the cost of the gas you’ll be putting in it, the cost of the oil is insignificant.

Don’t waste your money on synthetic oil; it won’t do a thing for the oil consumption. Buy the cheapest 20W50 for summer use and go to 10W40 or 5W40 in the winter, depending how cold your winters are.

I was going to convert over to amsoil 0w30 full synthetic in a couple days.

Won’t that be expensive in a vehicle that burns that much oil?
How will amsoil synthetic help the engine?

By the way, I too don’t think the consumption amount you noted is excessive.

Towing just about any trailer makes the engine work much harder. Your consumption of 2qts in 3K miles with some trailer towing in there isn’t bad. Others have given recommenddations regarding oil to use that makes sense.

I tow a 2 horse trailer, about 2,500 lbs empty and 4 to 5K with the horses, and a ski boat with a Toyota Sequoia. It doesn’t use oil normally but when towing I check the level frequently and use about 1 qt. per 1,000 miles.

I wouldn’t use 20W-50 oil in the engine. No matter the temperature above freezing, the oil will still flow like 20 weight oil when the engine is first started cold. And if you want to accelerate engine wear on cold starts, using a 20W-50 oil will most certainly accomplish that.


Tester’s reasoning is probably the only thing that would make it worth switching to synthetic, if only to get a 5W-50.

The clearances in these dinosaur engines, especially after 120K miles, are large enough to accommodate any issues presented by 20-50 oil…The 454 Chevy was about as loose an engine that was ever made…

0w-30 synthetic?? you might as well use water…Please let us know how often it blows through a quart of THAT !!

I am simply trying to extend the life of this engine as long as possible. I have A Jeep Cherokee and a Honda Odyssey that I have been running synthetics in for the last 120k, and they both have right around 190k on them with no issues. However, NEITHER of thoese use ANY oil between change interval, whether 5k or 7500 depending on whether Mobil 1 or Amsoil. I had heard that by running a full syn oil that it may decrease the oil consumption. It seems that the popular opinion here is that it will not improve the oil consumption at all. I am comforted by the fact that many of you feel that the rate of oil consumption that I have is not excessive. That is one of the things that I was hoping to find out by this post. The other is what type of oil seems to work best. So am I correct in thinking now, after reading all these posts, that a fully synthetic 20w50 would not prolong the the life the life of the engine?

Also, I have read some posts that suggest that the first quart that this engines goes through, disapears alot quicker than the 2nd quart would. Meaning that it would not consume oil as quickly once it reaches the ‘add’ mark. Haven’t tried this myself but read that a coupel times. Any thoughts?

Thanks in advance,


If you MUST use synthetic to prolong the engine life, go to 5W50, or 10W50 (not Amsol) so that it does not disappear like water vapor and put you in the poorhouse. This engine will last a very long time just using regular mineral oil. The oil consumption is not a function of rapid wear, it is inherent in this ancient design. Synthetic oil is extremely slippery and is recommended for high stress situations. But it slips though every nook and cranny.

Your present cars are lasting because you take good care of them, not because you are using synthic oil, unless you live in a very cold region and park outside.

We have many posters here who have ordinary cars with 300,000 miles on them using plain old cheap mileral oil, and having no oil consumption problems.

Don’t believe the Amsol hype; synthetics are oil for EXTREME (hot, cold, heavy loads) conditions only. Under normal driving conditions they have NO particular advantage and cost a lot more.

No matter the temperature above freezing, the oil will still flow like 20 weight oil when the engine is first started cold

No. It will produce no more stress than any other 20W @ -25F in terms of pumpability in the cold cranking simulator. It will heavier/thicker at any temp at any time than a comparable 20,30,40 WEIGHT oil. Cold properties aren’t related directly to viscosity. All the “W” means is that it IS pumpable at a given temp and not a semi-solid mass of jello spinning around in a circle around the pump gears.

My 454 would use oil routinely from new. Not nearly what the OP is talking about, but some.

I would make sure that the PCV system is in good condition. Change the valve …carb clean the hoses. I’d then consider Auto-Rx (www.auto-rx.com) to assure that the rings are not coked up. It doesn’t seem to bother it except under load.

If you don’t use Auto-Rx before putting the Amsoil SSO in there, do not be surprised if there is an INCREASE in consumption initially. Ever hear of someone switching to a new oil and going back since they realized more consumption? That is often due to different additive packages disrupting existing ring deposits and allowing more blow-by through until the rings are clear. It’s referred to as transitional consumption and usually occurs when going from one chemistry to another …like a conventional to a synthetic.

You also have to reason different kinds of consumption. Yours appears to be load related. Others are linear and some are progressive. The linear type consumption is more or less a static design/mechanical condition. Progressive consumption, where it increases the older the oil is, tends to point to a fatigue factor with the oil in question.

If using a conventional oil, I would use a 10w-30. If you want to see if consumption can be reduced with viscosity, then grab some 15w-40 mixed fleet oil.

…and check out Auto-Rx…