This just happened to pop in my mind today, different vehicles take different oil weights....but shouldn't current vehicles have clearances and tolerances so tight that there is no need for thick(er) oil like engines of the past? Case and point, Honda recommends 0w20 in my 2006 Accord 2.4, also recommended for the V6 3.0, yet the brand new VW's take a 40 weight? Is it just that their tolerances aren't as tight? Even the new Silverado's take a 0w20, and ford has been using 20 weights in there cars and trucks for years. So what gives?
Current vehicle oil requirements.....
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Sometimes different intended uses for vehicles will change oil requirements. My '14 Mustang specs 5W50 for the oil because it is a Track Pack, Ford assumes the car will be driven hard and see track time. Mustangs that have the 5.0 without the Track Pack spec 5W20 and the engines for both options are identical inside.
Originally Posted By: bdcardinal
Sometimes different intended uses for vehicles will change oil requirements. My '14 Mustang specs 5W50 for the oil because it is a Track Pack, Ford assumes the car will be driven hard and see track time. Mustangs that have the 5.0 without the Track Pack spec 5W20 and the engines for both options are identical inside.
Right, I can see why engineers might spec a thicker oil for a car that is going to be driven hard, but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
Sometimes different intended uses for vehicles will change oil requirements. My '14 Mustang specs 5W50 for the oil because it is a Track Pack, Ford assumes the car will be driven hard and see track time. Mustangs that have the 5.0 without the Track Pack spec 5W20 and the engines for both options are identical inside.
Right, I can see why engineers might spec a thicker oil for a car that is going to be driven hard, but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
What is the recommended oil change interval on your Accord?
Originally Posted By: Quattro Pete
What is the recommended oil change interval on your Accord?
It has a maintenance minder, 15% is recommended, 10% is change soon, 5% is change now, 0% is past due. Same engine without the MM is 5K miles or 6 months whichever comes first for severe and 10K miles or 1 year whichever comes first for normal. I am definitely in the severe category.
What is the recommended oil change interval on your Accord?
It has a maintenance minder, 15% is recommended, 10% is change soon, 5% is change now, 0% is past due. Same engine without the MM is 5K miles or 6 months whichever comes first for severe and 10K miles or 1 year whichever comes first for normal. I am definitely in the severe category.
Originally Posted By: gregk24
Right, I can see why engineers might spec a thicker oil for a car that is going to be driven hard, but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
Maybe its not needed, but the VW engineers believe 40 weight will provide the best engine protection. I'm sure an engine spec'ing 0w-20 would do just fine on a 40 wt too. I still think its more about ekeing out every last mpg for cafe standards versus engineering an engine with such tight tolerances that a 40 wt is just too thick to properly squeeze into those clearances and protect from wear.
Right, I can see why engineers might spec a thicker oil for a car that is going to be driven hard, but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
Maybe its not needed, but the VW engineers believe 40 weight will provide the best engine protection. I'm sure an engine spec'ing 0w-20 would do just fine on a 40 wt too. I still think its more about ekeing out every last mpg for cafe standards versus engineering an engine with such tight tolerances that a 40 wt is just too thick to properly squeeze into those clearances and protect from wear.
Originally Posted By: gregk24
but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
First, the Jetta doesn't mandate a 40-grade. It calls for an oil meeting VW 502.00 spec, and there are 30-grade oils that meet this spec.
Second, I believe some of this is carryover from Europe and the way the cars are operated and maintained there. Over there, high speed driving is typical, and I don't mean 75 mph. On top of that, standard oil change intervals are 20k km, or every 2 years. By recommending slightly heavier oil, VW builds in some safety buffer in case something bad (like fuel dilution) were to happen to the oil during such long OCI.
but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
First, the Jetta doesn't mandate a 40-grade. It calls for an oil meeting VW 502.00 spec, and there are 30-grade oils that meet this spec.
Second, I believe some of this is carryover from Europe and the way the cars are operated and maintained there. Over there, high speed driving is typical, and I don't mean 75 mph. On top of that, standard oil change intervals are 20k km, or every 2 years. By recommending slightly heavier oil, VW builds in some safety buffer in case something bad (like fuel dilution) were to happen to the oil during such long OCI.
Originally Posted By: Quattro Pete
Originally Posted By: gregk24
but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
First, the Jetta doesn't mandate a 40-grade. It calls for an oil meeting VW 502.00 spec, and there are 30-grade oils that meet this spec.
Second, I believe some of this is carryover from Europe and the way the cars are operated and maintained there. Over there, high speed driving is typical, and I don't mean 75 mph. On top of that, standard oil change intervals are 20k km, or every 2 years. By recommending slightly heavier oil, VW builds in some safety buffer in case something bad (like fuel dilution) were to happen to the oil during such long OCI.
Burn.....
Originally Posted By: gregk24
but cars like the Jetta with a 2.5? Just curious why a 40 weight would be needed.
First, the Jetta doesn't mandate a 40-grade. It calls for an oil meeting VW 502.00 spec, and there are 30-grade oils that meet this spec.
Second, I believe some of this is carryover from Europe and the way the cars are operated and maintained there. Over there, high speed driving is typical, and I don't mean 75 mph. On top of that, standard oil change intervals are 20k km, or every 2 years. By recommending slightly heavier oil, VW builds in some safety buffer in case something bad (like fuel dilution) were to happen to the oil during such long OCI.
Burn.....
IDK why VW's can run 5w-40, but I just read about a 66 GMC 305 V6 gasoline truck engine that was spec'd for sae20 heavy duty oil. This engine is overbuilt, lower rpm and low horsepower, and holds 10 quarts of oil. I expect compared to the 305, VW engines are not overbuilt, are high RPM and high horsepower and have smaller capacity sumps.
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The Jetta 2.5 has a 6.3 quart sump.
This is confusing because most US market oils do not meet the more stringent ACEA specifications from Europe. The synthetic oil sold in the US is no where near the quality of oil in Europe and requires very short drain intervals.
I did see an UOA report in a VW with 10W30 Napa synthetic and it was good with a thinner oil than recommended. (5,000 mile drain)
I did see an UOA report in a VW with 10W30 Napa synthetic and it was good with a thinner oil than recommended. (5,000 mile drain)
Originally Posted By: Dufus2
This is confusing because most US market oils do not meet the more stringent ACEA specifications from Europe.
Most do:
Summary Major US Synthetics
Not only do US made motor oils meet the same quality specifications as their European counterparts, in many cases they are exactly the same oil.
VW specifies needlessly heavy oils for reasons only VW comprehends.
This is confusing because most US market oils do not meet the more stringent ACEA specifications from Europe.
Most do:
Summary Major US Synthetics
Not only do US made motor oils meet the same quality specifications as their European counterparts, in many cases they are exactly the same oil.
VW specifies needlessly heavy oils for reasons only VW comprehends.
Thank-you for the chart. I've oftened wondered about the VW requirement for the 2.5L engine. I see no need for a heavy oil in this engine. BTW, just had my free 2nd yr. service @ VW dealer and they used Valovine MST oil. Not sure of grade but I believe it was 5w-30 since it can be bought in drums. If one were to do shorten OCI's, I would think any quality 5w-30 synthetic oil would be just w/the 2.5L engine. (12' Golf lists 5.8Qt capacity in owners manual.)
Originally Posted By: gregk24
.but shouldn't current vehicles have clearances and tolerances so tight that there is no need for thick(er) oil like engines of the past?
Yes, some engines have tighter clearances than 50 years ago. However, there are clearance limits that are very well known. No engine is substantially different from "normal limits" today. Oil viscosity requirements are largely for fuel efficiency reasons. Cold start improvements are also part of the reason.
.but shouldn't current vehicles have clearances and tolerances so tight that there is no need for thick(er) oil like engines of the past?
Yes, some engines have tighter clearances than 50 years ago. However, there are clearance limits that are very well known. No engine is substantially different from "normal limits" today. Oil viscosity requirements are largely for fuel efficiency reasons. Cold start improvements are also part of the reason.
In addition; engines that spec a 30 or 40 wt oil may use a 15,000 mile oil change interval and the manufacture expects the oil will shear down a grade or even two and still be "safe".
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