I've used Valvoline 10W40 in either conventional or high mileage formulations for the past 11 years on my 1986 Mercury Capri. It's got 221,000 miles on the little 2.3L OHC engine. I don't really have any issues with oil leakage since pretty much every gasket and seal has been replaced and the head was rebuilt. Would it hurt to go to a 5W30 or 10W30? I'd like to squeeze a little bit more economy out of the engine if I could. Any suggestions on a good weight, type, and brand of oil?
Going from 10W40 to something thinner???
- Thread starter ethangsmith
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Try GC; it won't let you down!
x2, what is the factory recommended spec for that engine? if it specs 10w40, with over 200,000 miles, i'd stay with that. if it specs thinner, then i'd give 10w30 a try
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Give it a test OCI with a Valvoline 5w-30 (whichever type of Valvoline floats your boat) and make your future selection(s) based on that test OCI. You won't hurt anything by going to a 5w-30.
I did put a Ranger roller cam in it to reduce friction. It is carbureted so I do get some small amounts of fuel in the oil too I am guessing. Owner's manual recommends SF 10W30 or 10W40. As a side note, what is "GC?"
The computer control system is long gone. I had too many issues with pinging and stalling with it. I put a Duraspark/MSD system on it and put a Motorcraft 5200 2 barrel (Same as Weber DFEV) on it at the same time. More reliable power but I'd like to get more than 18mpg around town!
Originally Posted By: TFB1
CG refers to German Castrol which is a 0W-30(only)weight... It should be a good choice for your 2.3 but not everyone stocks it...
And it's expensive, quite a change from VWB.
CG refers to German Castrol which is a 0W-30(only)weight... It should be a good choice for your 2.3 but not everyone stocks it...
And it's expensive, quite a change from VWB.
You should be getting much more than 18 mpg in town. I was getting 20+ with 200 I6 w/ single barrel carb and get 22 mpg city with 250 I6 in town w/ carb. 10w-30 should be just fine in those engines or even a blend 5w-30.
Heck, try Motorcraft 5W20 and see if it helps with mileage. Ain't gonna hurt anything for 3,000 miles with a car with over 200,000. I run that in my wife's grad am in the winter w/o problems and run 10-40 (1985) in the summer. Man if I had a car with that many miles I'd run Canola oil for 3,000 miles and post it here with a UOA!
Originally Posted By: ethangsmith
The computer control system is long gone. I had too many issues with pinging and stalling with it. I put a Duraspark/MSD system on it and put a Motorcraft 5200 2 barrel (Same as Weber DFEV) on it at the same time. More reliable power but I'd like to get more than 18mpg around town!
Years back Ford recommended setting the idle mixture till there was a slight roughness in the idle for best economy, I've always used the max vacuum at idle method myself... Still doesn't tell you what your A/F ratio is at part throttle cruse condition...
My bet is no oil is going to make a measurable difference, and only way to get a real improvement in fuel economy would be to convert it to the '87-'90 port system EFI... Unless you had a parts car no doubt not worth the cost/effort...
The computer control system is long gone. I had too many issues with pinging and stalling with it. I put a Duraspark/MSD system on it and put a Motorcraft 5200 2 barrel (Same as Weber DFEV) on it at the same time. More reliable power but I'd like to get more than 18mpg around town!
Years back Ford recommended setting the idle mixture till there was a slight roughness in the idle for best economy, I've always used the max vacuum at idle method myself... Still doesn't tell you what your A/F ratio is at part throttle cruse condition...
My bet is no oil is going to make a measurable difference, and only way to get a real improvement in fuel economy would be to convert it to the '87-'90 port system EFI... Unless you had a parts car no doubt not worth the cost/effort...
I've thought about EFI from the 87-93 cars, but that would involve more effort than what it's worth. Since the car was and is carbed, I would have to not only change out lots of intake and engine bay parts, but also run quite a bit of wiring and fuel lines. And I would have to put an EFI tank in too. Not worth the extra 2 horsepower the EFI engines had. When the old computer system worked, I got 20mpg around town and 30mpg on the highway. It declined quickly over the first years I owned it and it started stalling and pinging loudly. After tinkering with replacement parts and trying some recalibrations, I finally put in a roller cam, ditched all the electronics, ditched the 1 barrel for a 2 barrel, removed the air pump and converter (Which was TOTALLY clogged!), and redid the maze of vacuum lines into a few orderly sections. After all that, the car runs like its new, has good power delivery, and sounds healthy, but the fuel economy isn't too great. I've experimented with timing, jetting, and fuel enrichment to find that the car ALWAYS gets 18mpg. Go figure. As a side note, I may try some 5W30 in it. In the winter, it cranks really hard and the lifters clack loudly until the engine warms up.
The 1986 Mercury Capri 5.0 was a very nice car in its day; fuel injected too.
Originally Posted By: ethangsmith
I've thought about EFI from the 87-93 cars, but that would involve more effort than what it's worth. Since the car was and is carbed, I would have to not only change out lots of intake and engine bay parts, but also run quite a bit of wiring and fuel lines. And I would have to put an EFI tank in too. Not worth the extra 2 horsepower the EFI engines had.
Yeah I know about the wiring, I converted a '88 Turbo Coupe from the 2.3T to a Trick Flow headed 5.0, everything but the fuel tank had to be changed and the tank had to come off to install a larger flow pump... Even fuel lines were routed differently and had to be changed...
With EFI HP didn't change much but I believe torque increased significantly... We had manual transmission '86 & '87 Mustangs with the 2.3, the '87 definitely had more power and gave better fuel economy... Of course the '87 was 5-speed vs the 4-speed '86, so would have also played a roll in mileage... Those were the daughters cars, I had a '86 GT with the 5.0 & 5-speed...
BTW I only mentioned '87-'90 as the '91-'93 used the dual plug head and would require additional mods to install the later EFI system...
I've thought about EFI from the 87-93 cars, but that would involve more effort than what it's worth. Since the car was and is carbed, I would have to not only change out lots of intake and engine bay parts, but also run quite a bit of wiring and fuel lines. And I would have to put an EFI tank in too. Not worth the extra 2 horsepower the EFI engines had.
Yeah I know about the wiring, I converted a '88 Turbo Coupe from the 2.3T to a Trick Flow headed 5.0, everything but the fuel tank had to be changed and the tank had to come off to install a larger flow pump... Even fuel lines were routed differently and had to be changed...
With EFI HP didn't change much but I believe torque increased significantly... We had manual transmission '86 & '87 Mustangs with the 2.3, the '87 definitely had more power and gave better fuel economy... Of course the '87 was 5-speed vs the 4-speed '86, so would have also played a roll in mileage... Those were the daughters cars, I had a '86 GT with the 5.0 & 5-speed...
BTW I only mentioned '87-'90 as the '91-'93 used the dual plug head and would require additional mods to install the later EFI system...
Nice cars! As for the 91-93 cars, they are quite the strange animals. 8 spark plugs and DIS. I've heard though they put out 110hp, they are quite unreliable and often have coil pack failures. If I were to go EFI, I would go with the 2.3L turbo for sure. If I'm going to go through all the hassle, I want to at least have some power!
Getting back to the oil, I've always been told "Engines wear to the weight of oil being used." Another words, if I go to a thinner oil, since I was using 10W40, I will have lubrication and oil pressure issues. Is this true or will a 10 or 5W30 oil be ok?
Getting back to the oil, I've always been told "Engines wear to the weight of oil being used." Another words, if I go to a thinner oil, since I was using 10W40, I will have lubrication and oil pressure issues. Is this true or will a 10 or 5W30 oil be ok?
I would go to a thinner oil but never to a 20wt in this application. My preference is a good 5w30 from Pennzoil, Valvoline or Mobil. Ed
FWIW-
Owners manual says factory fill was API SF 10W30. According to the book, 10W30 or 10W40 should be used, except if the climate gets below zero degrees consistently, then 5W30 should be used. So should I go to a 10W30 or would a 5W30 still be safe? I don't want to kill this engine!
Owners manual says factory fill was API SF 10W30. According to the book, 10W30 or 10W40 should be used, except if the climate gets below zero degrees consistently, then 5W30 should be used. So should I go to a 10W30 or would a 5W30 still be safe? I don't want to kill this engine!
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