Wrong oil grade

[Cost Captain]

A technician at work today nearly put 10W40 oil in a ford, which needed 5W30, and it got me thinking... how much damage would using the wrong oil grade cause, under the assumption the level was kept correct.... and how long would it take for the damage to occur?

Luckily good ol' assistant manager saved the day and the fiesta will live on!

[filski666]

Cost Captain said:

A technician at work today nearly put 10W40 oil in a ford, which needed 5W30, and it got me thinking... how much damage would using the wrong oil grade cause, under the assumption the level was kept correct.... and how long would it take for the damage to occur?

Luckily good ol' assistant manager saved the day and the fiesta will live on!

unlikely to cause any damage unless it was really cold where the 10W40 is a bit thicker.

But to be honest the two grades are pretty similar in terms of viscosity, whether the other additives are up to requirements is a different matter - but it is not like they were about to put 85W90 Hypoid oil in!