Originally Posted by oil_film_movies
Don't forget fleet vehicles. Those vehicles in that market are partly sold on maintenance costs. It's true. I remember a conversation with a government fleet chief one time where he said the obvious: "When considering buying 400 of vehicle "A' vs. vehicle "B", we consider: 1. Purchase Price; 2. Maintenance Cost; 3. Residual value in 5 years; 4. Warrany Negotiated for this deal."
With that, allowing 5w20 allows you to use the cheapest Group2 oil you can scrape up. ...... A 0w20 is at least a syn blend and adds some cost. Not much to consumer John Q. Clueless, but it adds up in a competitive fleet deal, along with other things like tire replacement costs, etc., all that.
Some engines are more prone to causing permanent shear as well. The cheapest syn blend 0w20 has a thinner base oil and more VII.
Also, if the engine maker did their durability testing using 5w20, they are likely to recommend the same weight to buyers, especially if the "0w" part isn't considered a necessity with the oiling system.
It does appear GM has asserted their dexos1 0w20 these days though, since I don't know what new GM vehicle uses 5w20 any more.
I had a different experience when working in the government fleet industry. The fleet I worked for purchased vehicles - exclusively American manufacturers Chrysler, GM, Ford - and kept those vehicles until roughly 120,000 miles, then auctioned them. Oil was not a concern or consideration. Oil change intervals were 7,500 miles (based on testing/cost analysis) and conventional oil was used (5w30/5w20). There was never a concern of whether oil met specs or warranty considerations. The real concern was proprietary manufacturer information regarding engine management. If manufacturers would not provide that, which almost happened only once (Ford), their vehicles would not be purchased. We had to have their repair information - not just information from Alldata or Mitchell - but manufacturer proprietary repair training, scan tools, updates, access to their data. That was a must.
Tires were of no concern whatsoever, the government had a contract with Goodyear allowing us to purchase tires almost at cost. So cheap that the entire fleet would not purchase alignment machines because tire wear was of no concern, we'd just replace the tires. If something major came along and we absolutely needed an alignment, we'd sublet it out.
Surprisingly there was very little major engine failure or repairs due to the longer oil change intervals using only conventional. Most engine repairs came from Dexcool issue with intake gaskets (GM), vacuum leaks (Ford), EGR carbon buildup/check engine lights, evap leaks, crank sensors, gasket leaks...but very little internal engine issues. Chryslers were overall the worst, by far. Issues from bumper to bumper. But still very little engine issues, even with them. Transmissions?? Oh Chrysler...we would lose a Chrysler transmission almost once a week.
I saw a lot of fluid abuse in those years. Lol. Working in a fleet I really got to see the capabilities of fluids...and their ability to be abused and neglected. There were no considerations for fluid changes (outside of engine oil). Dexcool was the only coolant we'd usually change (only because of engine repairs/cooling system repairs). Ford never seemed to have coolant leaks - I remember thinking...wow, Ford at least has their cooling systems figured out compared to GM. The vehicles were taken out of service at 120,000 miles, so most likely the issues and problems from fluid neglect weren't felt until a little later. One thing I learned from working in a fleet, it's no nonsense, and they will push fluids to the max...and beyond.
