How often to change 20w50 Mineral

[FCD]

so i have a 1975 Ford Capri 3.0 V6 Ghia, around august 30th this year i switched from 10w40 simi synthetic to 20w50 mineral since it's what my Capri is supposed to run , i know the rule of thumb for most mineral oils is 3000 Miles but other people ahve told me to change it at least once a year even though i drive no more than 1500 / 2000 miles a year , the oil is Shell Helix 3 API SJ / CF
bieng a classic ofcourse it does burn some oil and gets maybe half a quart every month or so

 

[Atesz792]

Do you have an owner's manual? What does that suggest?

 

[FCD]

No i don't but i've asked around forums and everybody has told me they change it every 3000m or 5000km

 

[OneEyeJack]

... and then try a UOA so you'll be operating in the future with some actual information and feed back. Look at the cost of this UOA as education not an operating expense. Than share with us what you have learned.

 

[bigt61]

As much as you're topping off, I'd say you could go 5,000 miles easy - even if it takes you 3 years.

 

[ryanschillinger]

I change the 15w40 rotella in my old vehicles every 1 or 1.5 years because they don't get many miles. This time I used pennzoil high mileage 10w40 in the ltd to see how it does. I would say the best would probably be once a year but this last oci was closer to 1.5 years on the ltd because it's been doing a lot of sitting.

 

[TFB1]

Originally Posted By: bigt61
As much as you're topping off, I'd say you could go 5,000 miles easy - even if it takes you 3 years.


Agreed, I don't change my oldies more than every other year and have gone three or more...

I'd go to the 15W-40 or maybe the HM 10W-40 mentioned... Unless on it's last legs, no engine that isn't highly stressed(raced or operated at continual high RPMs), really needs 20W-50...

 

[HerrStig]

I would consider going back to mineral oil, so called, as going backwards.

 

[FCD]

I used to run Mobil 2000 10w40 , when i ran that the engine sounded like it had a lot of valvetrain noise ( flat tappet cam ) since i switched to Shell Hx3 20w50 mineral the engine runs better in every way , less noise , burns about half of the oil it used to , better oil pressure and it just feels a lot smoother , i live in Southern Spain where in summer temperatures get close to 100 F , I drive the car 2 - 3 times a week mixed city and highway driving , i used to have to top it off every 3 weeks with the 10w40 , now i just top it off every month and a half, and i'm going to keep running 20w50 because i'm pretty sure it is what Ford reccomended for this engine in hot climates even when new 10w40 was for cold climates and pretty much everybody i've asked uses it on these engines even when they have just been rebuilt.

And since this is the only oil i can get here that for sure has the required ZDDP for my engine there's no chance of me going back to 10w40 i will though try Valvoline VR1 20w50

 

[Greasymechtech]

Stick with 20w50. Plenty of carb fuel dilution to deal with.

With oil consumption that high, change the oil every 2 years.

Post some pictures of the scenic islands.

 

[Pontual]

Father in law likes to use dino 20w50 sj in a synthetic sj (Esso Ultron or TOTAL QUARTZ 9000 5w40) oil req car a 2001 Citroen C5, with a PSA EW10J4 2.0 16v DOHC gasoline engine. It got some copper color varnish at the heads, no sludge. But the wearing if fine at 110k miles of city. But the factory OCI is 15k miles and he does 10k miles on the mineral molasses... Gentle driving helps a lot, in this case.

 

[Shannow]

For the carbed cars of the '70s, 5,000km was the recommended OCI, as mentioned previously, as much to do with fuel as anything.

if it takes you 2 years to do it, as long as it's decently warmed up the majority of runs, should be OK.

 

[Merkava_4]

That's a good looking car.

 

[BrocLuno]

There is absolutely no proof I can find that Syn is actually better than well refined Dino Oil... Since we can get an engine of this vintage to 200,000 miles on Dino Oil, where is the advantage to more expensive Syn's?

Change it at the beginning of summer as the heat is your biggest enemy. New oil for the hot times will get you through to next year easy. It's cheap enough and motors aren't ...

 

[FCD]

I think i'll change the oil before every summer then since here in South Spain the heat of the summer months is pretty brutal on classic cars and i can buy new genuine motorcraft EFL90 filters frm Ford or online prety easily
Merkava that one is a 1986 model mine is a 1975 which is a bit different , these were also sold in north america from until 1977 as the Mercury Capri
This is mine:

 

[zeng]

In Malaysia with Euro II gasoline of 500 ppm Sulfur content, all mechanics here recommends 20W50 at 5000 km OCI for high mileage carburreted as well as MPI Japanese engines.

No issues of sludge .

Some owners even go up to 8000 km , with observable varnish at rockers.

Edit: The ambients here is low of 24*C to highs of 33*C year round.

 

[FCD]

with the 10w40 i went over 2 years with no changes just top offs and last december i pulled the rocker covers to adjust the valve clearances and it was surprisingly clean with no signs of varnish or sludge

 

[alcyon]

instead of shell helix HX3 20W-50, why don't you try Pennzoil Yellow Bottle 20W-50. My friend used the HX3 and it varnished his engine. My take on it is Shell kept with the old outdated formula for this line of ultra low cost oils. Pennzoil on the other hand has improved their formula even for the 20W-50.
I would recommend the US made Pennzoil though, not your local blended one, which you could get from your local ACE hardware.
My dad used to have a Mk2 escort, I always wished he would have bought the capri instead, it was more sporty looking.
The bottle should look like this.

 

[FCD]

I can't get Pennzoil here in Spain and I use Hx3 because it is the only oil I can find here that for sure has the required Zddp for a flat tappet camshaft like the one in my Capri...

 

[Bamaro]

FWIW - Mineral oil:
Quote:
A mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum.

The name mineral oil by itself is imprecise, having been used for many specific oils over the past few centuries. Other names, similarly imprecise, include white oil, liquid paraffin, pariffinum liquidum (Latin), and liquid petroleum. Baby oil is a perfumed mineral oil.

Most often, mineral oil is a liquid by-product of refining crude oil to make gasoline and other petroleum products. This type of mineral oil is a transparent, colorless oil composed mainly of alkanes and cycloalkanes, related to petroleum jelly. It has a density of around 0.8 g/cm3.
https://en.wikipedia.org/wiki/Mineral_oil

I'm not trying to be the dictionary police but on a site like this we really shouldn't refer to automotive oil as mineral oil.