Oil viscosity for early 90's Ford V8?

I bought my son a 92 Crown Vic. No owner’s manual. I sort of think I remember that the recommendation is 10W30, maybe straight 30 in a hot summer, but I am not sure. Anyone know? 4.7 L V8.

Ford Motor Company recommends either 5W20 or 5W30 oil for that engine.


It’s a 4.6L and The recommended oil is 5W-30. They do recomended 5W-20 for the newer 4.6L engines, and they did change their recommendation from 5W-30 to 5W-20 or some engines at some point, but I think that The 1992 models still called for 5W-30. I would definately not use straight 30 weight in this car.

In the early 90s there was no such thing as 5W20, according to all the oil manuals I have. I would defintely go with 5W30 for this car. You can use a 0W30 synthetic in the winter if you live in a cold area. But if there is a good deal of wear on the engine, I would not do it since it will consume that expensive oil.

In 2007 I had a Ford Explorer for a construction project. The manual had two different recommendations; 5W20 for one engine and 5W30 for the other. I don’t recall which one, V6 or V8. The point here was that Ford would not rcommend 5W20 for their older engines since the larger clearances would lead to excessive oil consumption.

Ford put out TSB a few years ago about the time 5W-20 came out, retroactively changing the recommneded viscosity from 5W-30 to 5W-20 for some engines.

It will LOVE 10-30 in the summer and 5-20 in the winter. It will not complain about straight 30 in hot climates either…But this is true for almost ANY engine…

This is the first model year for this engine/car…They still make “improved” versions of the same car today but the '92 models were very sound and reliable. They are a little lighter than the newer ones, so they get excellent gas mileage, many examples achieving 28mpg on the highway…By now, on many of them, the valve stem seals have failed so they burn a little oil, but oil is cheap and it doesn’t seem to bother them. The EGR supply tubing is small (and difficult to change) so you may get an “EGR low flow” code and a check engine light. Drive on…

Can anyone remember the last time a car was made that used a single viscosity oil? I can’t.

I think it would be a bad idea to use single weight 30 oil in your Crown Vic. I would go with 5W-30 or 5W-20 like others have recommended.

The owner’s manual of my 1965 Dodge Dart had 5 PAGES on “Engine Oil Recommendations” stressing the importance of ambient temperature on oil selection. It shows for the 273 V8:

  1. Single Grades; SAE30 where temperatures are consistently ABOVE 32F, and SAE 10W where temperatures range from -10F to 32F. No single grade 5W, since that would go through the engine too fast.

  2. For Multigrades; SAE 20W40 where temperatures are consistently above 32F, SAE 10W30 for year round use.

Oil changes were recommended at every 4000 miles or 3 months.

For my 1966 Chevelle Malibu,in additon to the normal multigrades, the single grades of 10W and 20W were for below freezing and above freezing respectively. Oil change itervals were 30 days below 0 degrees F, and 60 days for all other operation; no mileage was given, except that the oil filter should not be used more than 6000 miles. I changed oil and filter every 3000 miles.

Multigrade oils in those days were not great in terms of quality control and hence the option to use single grades. But then in those days you normally needed an overhaul at 150,000 miles, if you were lucky.

In tropical countries, multi-grade oil can be hard to find on store shelves. There is just no reason to use it. For cars delivered in these areas, the owners manuals make the necessary adjustments to recommend what is available…

Americans think the entire universe revolves around their preferences and customs. It does not. Blazing across Mexico, a quart of H.D. 30 oil will satisfy the needs of virtually every car engine ever made…The rest is mostly marketing, mark-ups, margins, hype and shelf-space…

Living in hot south florida I’ve been using straight 30w oil for 20 years in my 89 mustang GT 5.0, 59 T-bird (390 4bbl) and 74 Nova (250 I-6). All 3 vehicles are in car show condition.

I have never had an engine failure using straight 30w all year round. The multi-grade oils now have very low zddp content and can cause cam failures on older engines with flat tappets. Ex: 74 Nova & 59 T-Bird, The GT has roller lifters.

Some oil manufactures have even removed all the zddp, and only allowed a maximum of 800ppm which is too low for older flat tappet engines which require a minimum of 1100 ppm.

A lot of synthetics now contain 0 % zinc.

Castrol 30w HD contains 1350ppm of zddp, where Valvoline 20w-50 racing oil contains 1500ppm.

Straight weight & racing oils do not fall under the EPA requirement for reduced zddp to protect catalytic converters.

Straight weight oils is all oil with no viscosity improvers.

Would I use straight a weight oil in a new vehicle under warranty ?..not hardly. Would use what the owners manual says. If temps were constantly over 90 degrees I might go up one notch in viscosity say from a 5w-30 to a 10w-30 not to void a new car warranty.

For many years, I ran 15-40 fleet oil in every 4-stroke engine I owned, which at times was a considerable number. It is STILL the best overall engine lubricant on the market. And as you pointed out, this product still contains adequate zinc to protect steel against steel surfaces. CJ-4 and SM certified.

The 15W40 grade is still the preferred oil for heavy duty trucks and I would recommend it for trailer towing with pickups and SUVs. Just don’t use it in the winter without having a block heater.

In rural Puebla, Mexico, I looked at Aurerra (Wal-mart subsidiary) for 5W30 and all they; had on the shelves was 20W50. I do not believe 5W30 or 10W30 is wrong for the temperatures they experience in that area, from 35 F. to 95 F. year round. I live mostly in southern Texas and Mexico in moderate mountain temps and I have used 10W30 for all 162,000 miles. If I lived in Sonora, I would consider 20W50…