Burning ~3 quarts of oil between changes

[Redrig]

As the title states, my daily driver is burning a lot of oil. This is nothing new, she's old and tired and has 250,000 miles on the clock. Still drives just fine . Pvc is fine . Yada yada. I change the oil every 3k bit probably average adding about 3 quarts between changes .

It's a 91 Ford bronco with a 302. I'm working on a replacement engine

But my question is how thick is too thick? I live in Utah and I generally run 10w40 year round. But dang I am getting tired of adding oil frequently.

I've heard of running too thick of oil can twist your distributor shaft, do you think 20w50 is safe to run in the summertime ? Or straight sae40 weight? Lucas , Idk

Any thoughts . Thanks in advance

 

[airshot]

Add some STP to your oil, switch to a heavy oil like a 20-50 in warm weather. How much is burning and how much is leaking ??

 

[Redrig]

Sorry should have clarified . No leaks . Or extremely minimal leaks anyway. Is 20w50 too thick ? I looked at some and it was like cold syrup.

 

[Scott Danforth]

I would switch to 15w40, however it wont slow the burn much

 

[Renken2000Classic]

I tried 20W-50 once in my '89 GMC 4.3L for the same reason (only using about 3x that much), and it boiled the coolant. Back to straight 30 or whatever I have.

That was given as an option in the owner's manual too.

It's sitting in the driveway waiting for me to replace the slave cylinder now, since the son who had been borrowing it when that went doesn't seem inclined or is too busy or whatever...

 

[Redrig]

I did an oil change of the rotella 15-40 this weekend. We will see if this changes that burn rate at all

 

[airshot]

Time for a rebuild or reman engine...

 

[Scott06]

I don't think heavier oil will help much but usually use oil pressure to determine if you can go heavier weight. You can put a mechanical gauge on and judge if you can tolerate heavier oil or not. when too heavy an oil is used for the bearing clearances that's when oil pump drives get damages.

Also if you are putting 3 qts in over 3 k miles you can extend your change interval a bit as you are freshening the oil as you go. You will not gain any engine life over a 5 k change interval at this point

 

[dolluper]

Have you investigated to find the problem? You say it runs fine sounds fishy...Unless its just valve seals... Do a compression check at least to get a clue before replacing with maybe a better one.

 

[Redrig]

Yeah , I did a compression test a few years ago. It was low but even , around 110 or 120 on all if I remember right and it's certainly down on power. My 3500 pound boat and trailer kill it going over mountain passes .

I don't know if there is any one particular thing . There are no ticks or anything. It's a good daily driver overall , just getting tired .

I am strategizing a new engine for it

 

[Scott Danforth]

I am strategizing a new engine for it

I would look at stroking your current block to a 348. Talk to your local machine shop

 

[Redrig]

I would look at stroking your current block to a 348. Talk to your local machine shop

Would love to . There's a well rated one close by .....The problem is they are at least 6 months out right now .

 

[airshot]

I did an oil change of the rotella 15-40 this weekend. We will see if this changes that burn rate at all

Probably not, time to go shopping at the junkyard. There are many good motors out there where folks have just totaled out the vehicle itself. Replaced quite a few engines with junkyard engines over my many years of driving, only ever had one bad one from a junkyard....

 

[Redrig]

I found a pretty good possibility , I found a 96 explorer 302 with the GT40 heads and apparently it has only 80k miles on it. So this would be a "better" 302 than whats in my Bronco anways. they sent vids of the engine running before they pulled it and sounded decent at least from what you can tell on a video.

what I am thinking is to buy that engine , dissassemble , take the heads into have them cleaned up and redone .

I have read that the bottom end "should be" okay at that mileage. but my question is...... are there tools or measuring devices / strategies to indeed check if a bottom end is good once you have the heads off ? Can you do a compression check without an engine installed ? OR just have the whole thing rebuilt ?

I have never torn into an engine very far , a timing chain is as deep as I have ever been , but I think this would be a fun project to put together in my garage with assistance from a machine shop (and of course you all - haha)

Thanks in advance for any thoughts.

 

[Scott Danforth]

Do a compression check.

If you pull the heads, look at the ridge. If you can catch a nail on it, then rebuild.

Pull the pan and plastigage the bearings.

At 80k, I would probably only borescope the cylinders when I went to look at it

 

[matt167]

I would put 20w50 in it. I would be the guy that put a 4.8 or 5.3 LS engine in it with a standalone controller. Slight bit of work but it drops in with conversion mounts

 

[dolluper]

Sure just hook up a starter to it with a remote switch and do a compression test... Out of the vehicle with engine supported. Do it before you pull the heads or anything else with the donor engine just to see if its worth your time . lf compression is good drop it in and go driving.

 

[FishEpperson]

I would add Lucas Oil stabalizer to it

 

[Redrig]

Thanks for replies everyone .

I was able to find a 302 locally that was intended for a 67 mustang restoration , but the guy opted to go with a 351 and stroke it . So I picked it up for 200 bucks stand included .

Allegedly the engine is from a 89 mustang HO and is pretty good shape from what I can tell . I have most of it torn down , but the rotating assembly is still in the block . The cylinder walls don't have any gouges and still have factory crosshatch. No ridge at the top.

The plan from here is to take the short block into a machine shop and have them inspect everything to see if it needs bored or whatever.

The heads are junkers , but the pistons are pretty sought after as they are factory forged ones .

After that , I just need to decide on what heads and what cam to throw in it .

 

[Redrig]