Volvo Owners Club Forum - View Single Post - D5 (D5244T to 2005)

AndyV7o · Jun 2nd, 2018, 13:45

A5/B5 was specced on euro4 and later engines, post 2005/6
A4/B4 was specced for the euro3

I dont know whether Volvo made any internal alterations on the euro4 to safely allow the use of a B5 oil, or whether they thought 'sod it, they're renowned to outlast the bodyshell, even if they do 1/3 the miles before dying, itll be long after its our problem',
BUT
You Do Not want to use a B5 oil in an engine specced for B4! They have differing HTHS values (dynamic viscosity, the actual body of oil that parts 'float' upon to prevent metal to metal contact) meaning that a B5 oil cannot bear the load placed upon it unless the engine is specifically engineered to make use of its properties, whilst a B4 can. Thus you risk metal to metal contact under load in using a B5 in an engine that isnt dedigned for it. You may, however, use oils to C3 spec as this is the equivalent to B4 but with lower saps (the dirty by-product that clogs dpf's and sometimes cats).
It isnt quite as black and white as I make it sound, but to elaborate further gets into deep bewildering science that can confuse more than clarify!

Furthermore I have read elsewhere that volvo changed the requirement from 0w30 to 5w30 following a bulletin they sent ti dealerships, though seriously 0w is fine.
0w30 5w30 0w40 5w40 to B4 or C3 will all be fine for a euro 3, same grades but B5/C2 for euro 4. If using a C spec, ensure its from one of the big names (mobil, castrol, shell, millers, fuchs, motul, gulf) and dont run extended drain intervals, stick to 12 month/10-12k max. (Though extended oci's are best avoided anyway)

A5/B5 does not supercede A4/B4. A4/B4 (kind of) supercedes A3/B3, whereas A5/B5 (kind of) supercedes A1/B1. A5/B5 is not a newer spec following on from A4/B4 but an inherently differing oil in its functionality and behaviour.

Hope this helps!

Jun 2nd, 2018, 13:45	#16
AndyV7o Premier Member Last Online: Jun 21st, 2021 20:47 Join Date: Jun 2018 Location: Creswell	A5/B5 was specced on euro4 and later engines, post 2005/6 A4/B4 was specced for the euro3 I dont know whether Volvo made any internal alterations on the euro4 to safely allow the use of a B5 oil, or whether they thought 'sod it, they're renowned to outlast the bodyshell, even if they do 1/3 the miles before dying, itll be long after its our problem', BUT You Do Not want to use a B5 oil in an engine specced for B4! They have differing HTHS values (dynamic viscosity, the actual body of oil that parts 'float' upon to prevent metal to metal contact) meaning that a B5 oil cannot bear the load placed upon it unless the engine is specifically engineered to make use of its properties, whilst a B4 can. Thus you risk metal to metal contact under load in using a B5 in an engine that isnt dedigned for it. You may, however, use oils to C3 spec as this is the equivalent to B4 but with lower saps (the dirty by-product that clogs dpf's and sometimes cats). It isnt quite as black and white as I make it sound, but to elaborate further gets into deep bewildering science that can confuse more than clarify! Furthermore I have read elsewhere that volvo changed the requirement from 0w30 to 5w30 following a bulletin they sent ti dealerships, though seriously 0w is fine. 0w30 5w30 0w40 5w40 to B4 or C3 will all be fine for a euro 3, same grades but B5/C2 for euro 4. If using a C spec, ensure its from one of the big names (mobil, castrol, shell, millers, fuchs, motul, gulf) and dont run extended drain intervals, stick to 12 month/10-12k max. (Though extended oci's are best avoided anyway) A5/B5 does not supercede A4/B4. A4/B4 (kind of) supercedes A3/B3, whereas A5/B5 (kind of) supercedes A1/B1. A5/B5 is not a newer spec following on from A4/B4 but an inherently differing oil in its functionality and behaviour. Hope this helps! Last edited by AndyV7o; Jun 2nd, 2018 at 14:34.