Both bottles say 5W, and that part means the same thing on each: both meet the same SAE winter rating, the limits for cranking and pumping when the engine is cold (the W is for winter). The second number is the difference. It grades how thick the oil stays at normal operating temperature, and 5W-30 stays thicker than 5W-20.

5W-205W-30
Winter rating (the "5W")Same SAE 5W categorySame SAE 5W category
Thickness when hotThinnerThicker
Where you see it in our trucksF-150 5.0 to 2020, Ram 5.7 HEMI, Tundra 5.7 to 2011F-150 EcoBoost, F-150 5.0 from 2021, Super Duty 6.2 from 2016

The viscosity grade is also only half of the specification. Manuals add a quality standard: Toyota's 2024 Tacoma manual asks for ILSAC GF-6A oil, Ram's 2009 heavy-duty manual for "API Certified" oil, Chevrolet for dexos1. Two bottles with the same grade are not automatically interchangeable if only one carries the approval your manual lists.

The useful question, then, is which grade and which approval your engine was designed around. The answer is not a matter of taste or forum consensus. It is printed in the owner's manual, and it has moved around more than you might expect.

Checking the oil level on the dipstick. The grade on the bottle matters as much as the level.
Checking the oil level on the dipstick. The grade on the bottle matters as much as the level. Photo: Environmental Protection Agency. 12/2/1970, Public domain

The same engine, two answers

The Ford F-150's 5.0L V8 is the best example. Ford's manuals call for SAE 5W-20 from 2014 through 2020, then SAE 5W-30 from 2021 on. If you have owned both, or you are buying used, the year matters more than the engine name. The EcoBoost V6s, by contrast, have been 5W-30 the whole time, and the 3.3L V6 stayed on 5W-20.

2007201020132016201920222025F-150 5.0L V85W-205W-30F-150 3.5L EcoBoost5W-30Super Duty 6.2L V85W-30Silverado 1500 5.3L V80W-20Tundra 5.7L V85W-200W-20Ram 5.7L HEMI*5W-205W-205W-300W-20Grade printed in each owner's manual; gaps: no figure shown. *Ram 2500/3500 over 14,000 lb GCWR: 5W-30 through 2016; 2026: Ram 1500.

The Super Duty's 6.2L gas V8 made the same move to a thicker grade, from 5W-20 to 5W-30 for 2016. Other engines went the opposite way, to thinner 0W-20: the Tundra's 5.7L for 2012, Chevrolet's 5.3L and 6.2L V8s in the generation after 2012 (from 5W-30), and the Ram 1500's 5.7L HEMI, which was a 5W-20 engine through 2020 and is listed at 0W-20 in the 2026 manual. The older Tacoma 4.0L V6 called for 5W-30 throughout.

EngineModel yearsGrade in the manual
F-150 5.0L V82014-20205W-20
F-150 5.0L V82021-20265W-30
F-150 2.7L / 3.5L EcoBoost2015-2026 / 2014-20265W-30
Super Duty 6.2L V82014-2015 / 2016-20225W-20, then 5W-30
Silverado 1500 5.3L / 6.2L2011-2012 / 2014-20215W-30, then 0W-20
Tundra 5.7L V82007-2011 / 2012-20215W-20, then 0W-20
Tacoma 4.0L V62005-20155W-30
Ram 5.7L HEMI2009-20205W-20 (2500/3500 over 14,000 lb GCWR: 5W-30, through 2016)
Ram 1500 5.7L HEMI20260W-20

So there isn't a "truck oil". Some engines moved to thinner grades, some to thicker ones, and the change often lands with a new model year rather than a new engine name. The only safe rule is to look up yours.

When the manual gives two grades

Some manuals tie the choice to how the truck is used, and those are the most interesting cases, because they show what the second number is for. Ram's 2009 manual for the 2500 and 3500 lists the 5.7L HEMI at SAE 5W-20 "for trucks operating under a gross combined weight rating less than 14,000 lbs" and SAE 5W-30 "for 2500/3500 trucks operating under a gross combined weight rating greater than 14,000 lbs". Ram kept printing that split in its manuals through 2016. More work, more heat, thicker oil. (If GCWR is new to you, here is what it means.)

Toyota allows a stopgap in the other direction. The 2024 Tacoma manual says:

"If SAE 0W-20 is not available, SAE 5W-20 oil may be used. However, it must be replaced with SAE 0W-20 at the next oil change."

Notice what it does not offer: 5W-30.

Can I use 5W-30 instead of 5W-20?

Our ruleUse the grade and the approval your manual lists for your model year and engine. Use another grade only when the manual says you may, and only on its terms.

Some manuals do give you room. Toyota's lets you run 5W-20 when 0W-20 is not available, as long as you go back to 0W-20 at the next change. Ram's older manuals offer 5W-30 for heavy towing. Those permissions are specific to an engine and a situation; they are not a general license to swap grades, and a manual that lists one grade has not approved the other.

If you are stuck with a low dipstick and the wrong bottle, that is a question for your manual or your dealer, not a forum. For the regular change, stick to the specification. Modern engines with variable cam timing are calibrated with a specific oil in mind, and the warranty conversation goes much better when the receipt matches the manual. If you tow hard and your manual offers a heavier grade for that use, that's the one case where we'd pick the thicker option on purpose.

The grade is half of an oil change. The other half is the amount, and it varies more than you would expect between engines and years. Capacities with filter, each with the manual page it comes from: F-150, Super Duty, Silverado 1500, Tundra, Tacoma, and by engine: 5.7 HEMI, 6.7 Power Stroke and 6.7 Cummins.

Sources

Exact pages for every year are on each truck's oil capacity page.