IPD sale Volvo Parts
Did you know? 🤔
Logged in users can get email notification of topic replies Log in or register (free).
Amazon Link Buy your stuff using this and it helps MVS!

2009 xc90 3.2 awd Better gas mileage in the summer but not in the winter WHY?

Help, Advice, Owners' Discussion and DIY Tutorials on Volvo XC90s. The XC90 proved to be very popular, and very good for Volvo's sales numbers, since its introduction in model year 2003 (North America).
User avatar
MoVolvos
Posts: 1554
Joined: Sun Jan 15, 2012 6:47 pm
Year and Model: 03S80T6~08C30T5
Location: NC
Has thanked: 6 times
Been thanked: 15 times
United States of America
MoVolvos

Re: 2009 xc90 3.2 awd Better gas mileage in the summer but not in the winter WHY?

Post by MoVolvos » Sun Jul 14, 2019 12:16 am

-
I used to use a 15-40W motor oil year round in all my cars. When I used it in the 98 S70 T5 the car would take a little more time to warm up in the winter and not as swift. No running issues just feel weighted and mileage suffered a little.


-

Blessings,

BKM

1998 S70 T5 - Donated
2003 S80 T6
2003 GS300
2003 Odyssey
2008 C30 T5
2019 Atlas SE 4 Motion

User avatar
E Showell
Posts: 2665
Joined: Thu Oct 16, 2008 4:00 pm
Year and Model: V70R '06 AWD Auto
Location: Long Valley, N.J.
Has thanked: 4 times
Been thanked: 28 times
United States of America
E Showell

Re: 2009 xc90 3.2 awd Better gas mileage in the summer but not in the winter WHY?

Post by E Showell » Sun Jul 14, 2019 6:37 am

Gas for the winter is formulated differently than summer blend to reduce air pollution. That difference accounts for the discrepancy in summer/winter mileage & performance. This is well-understood and you can probably find a decent amount written about it. From what I understand, it has to do with Reid Vapor Pressure -- what we commoners might think of as evaporability. Basically, gas need to evaporate more easily in the winter with lower temperatures so starting in cold weather isn't overly difficult, whereas in summer, we don't want gas evaporating excessively in the atmosphere thereby increasing air pollution.


'98 V70 NA FWD 5 spd, silver sand metallic (sold)
'99 V70 NA FWD Auto, dark blue (soon to be for sale)
'99 S70 NA FWD Auto, black (sold and resurrected)
'07 S80 3.2 FWD Auto, Barents Blue Metallic
'06 V70 R AWD Auto, Sonic Blue Metallic
'04 XC70 Ruby Red Metallic

Post Reply