5W50

[glasgow]

5W50 oil is good for high RPM. But is there any draw back (as compared to for example 5W30 or 10W40)? How about performance at  winter's freezing temp?

Regards

Ahmed

[Geoff Brown]

It is the standard oil for my R400D.

No problems summer or winter just allow the engine to come to temperature + 10 minutes of 'carefull' rev management (especially in winter), then drive the nuts off it!!

Cold oil pressure in winter will of course be slightly higher than normal for a short while so take it easy.

[Roger Ford]

Will it? I thought the 5W was the cold viscosity. Hence it should be the same as a 5W30 and thinner than a 10W40.

[Bob L]

Ditto - thought 5W50 would cover both high and low temperatures better than 10W40 etc

 

Now watch someone prove me wrong.......

[glasgow]

if 5W50 is covering both high and low rtemp better, why it is not used for all cars? why 5w30 and 10W40 still have a market? Can't be just explained by costs.

[Jonathan Kay]

Because different engines need different viscosity lubricant. Factors include oil pumping system and clearance on crucial bits like bearings. Too little viscosity and it doesn't lubricate, too much and it doesn't get there.

Jonathan

[glasgow]

OK, Jonathan, but this doesn't explain why CC recommend 5W50 for track cars and not for road cars.

 

[martyn]

I dont think they're saying that 5w50 works equally well at both high and low temperatures.  5w50 will achieve the correct hot viscosity at a higher temperature than a 5w30.  Thats why it is better suited for high revving usage as the average temperature will be higher.  Roger's point is that they both have the same cold rating (5w) so therefore should have similar cold start properties (regardless of how the oil behaves once warmed up).

[Jonathan Kay]

Glasgow: What engine are we talking about, and what are the two recommendations?

Thanks

Jonathan

[glasgow]

Car is 1.8L k Rover, 2003. Manual says: 

"All cars: Comma Syner-Z synthetic 0W-40....... Performance/Track Driving: Caterham motorsport 5W-50"

[Jonathan Kay]

Thanks.

I assume the higher viscosity at the hot end is because they know the engines will be hotter on the track and the other oil would get too thin. I have no idea why they have recommended different viscosities at the cold end, but it might be due to what was available at some time rather than what was needed.

Jonathan

[Martin J]

5W30 for my sigma as recommended by Ford & Caterham.

It is so runny compared tothe 20W50 I used to tip into my Minis years ago.

[anthonym]

I've used 5w50 in my R500K for 14 years; almost no track use.