Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Greenbay packer on 13 May 2010, 11:42:07

Title: Correct engine oil for 2.5 V6?
Post by: Greenbay packer on 13 May 2010, 11:42:07
Could someone confirm that a 10W-40 semi synthetic oil is the  correct oil to use on a 1998 2.5 V6?  I've always thought it was, but have recently seen references to 5W-40 and 15W-40's being used.

Also, are Unipart and Halfords own oils ok to use?

Thanks for any replies.

Title: Re: Correct engine oil for 2.5 V6?
Post by: Darth Loo-knee on 13 May 2010, 11:45:09
Vauxhall 10-40 Semi Synthetic :y
Title: Re: Correct engine oil for 2.5 V6?
Post by: Elite Pete on 13 May 2010, 11:47:47
Spend £20 on a member ship to Autobahn Stormers and they will send you a Trade Card you can then buy your Vauxhall service items including oil much cheaper than the Halfords stuff ;)
Title: Re: Correct engine oil for 2.5 V6?
Post by: henryd on 13 May 2010, 11:51:22
autodata list; cold climate  5w30
                moderate climate 15w40
                     hot climate    20w40
alternative moderate climate  10w40 semi synthetic

don't know about halfords oils but I use a lot of unipart oils and have had no issues
Title: Re: Correct engine oil for 2.5 V6?
Post by: Greenbay packer on 13 May 2010, 13:59:37
Thanks for the info - that Autobahn Stormers card sounds useful, I'll definitely look into that  :)!
Title: Re: Correct engine oil for 2.5 V6?
Post by: I_want_an_Omega on 13 May 2010, 14:38:42
Ok "Mr Cheesehead" - having spent most of 1997 in the Chicago area I think you should explain to the Forum your OOF name and what I've just callled you.

I have to say I found it most amusing to see  ;D ;D ;D ;D ;D ;D
Title: Re: Correct engine oil for 2.5 V6?
Post by: Greenbay packer on 13 May 2010, 21:02:54
Not at Soldier field supporting them Pussies - I mean Bears I hope?
Title: Re: Correct engine oil for 2.5 V6?
Post by: I_want_an_Omega on 13 May 2010, 22:23:58
Not all interested in the sports side of things ........

Just amazed at the headwear the fans wear! Why?

Dare you to post a picture .............
Title: Re: Correct engine oil for 2.5 V6?
Post by: Bose Addict on 14 May 2010, 09:26:46
'always used 10-40 semi-synthetic as advised above until a main dealer insisted on using Vauxhall fully Synthetic (0-40 I think) last year.  I have to say it made a difference, quieter running, especially cold starts.   :y Extortionate price though........ :(
Title: Re: Correct engine oil for 2.5 V6?
Post by: Andy H on 14 May 2010, 10:30:53
I switched to using 5w30 fully synthetic a few years ago because 10w40 is just too thick in a cold engine. It leaves the tappets sounding like a castanet player having an epileptic fit after a cold start and puts unnecessary strain on the oil pump.

2 stroke oil in use nowadays is almost all fully synthetic because it produces much less ash/soot deposits than mineral oil. My thinking is that synthetic 4 stroke oil will result in a cleaner engine for the same reason.

I'm willing to accept that I may be totally wrong but the same people who religiously advocate 10w40 semi-synth also seem to spend their weekends unblocking engine breathers, fixing noisy tappets and diagnosing terminal engine failures that seem to be caused by lubrication failure :(

The clincher for me is that last time I changed the oil VX were running a 'buy 3 get 1 free' offer which meant 4x 5 litres of 5w30 for £50 using my ABS membership :y
Title: Re: Correct engine oil for 2.5 V6?
Post by: Andy H on 14 May 2010, 10:35:41
Apparently VX are still running the 4 for 3 offer.

5W30 dexos2, 5 litre part number 93165557
Offer price for four cans £50.10
Equivalent to £2.51/litre

10W40 Semi synthetic, 5 litre part number 93165216
Offer price for four cans £32.67       
Equivalent to £1.63/litre
Title: Re: Correct engine oil for 2.5 V6?
Post by: TheBoy on 14 May 2010, 13:00:03
Quote
I switched to using 5w30 fully synthetic a few years ago because 10w40 is just too thick in a cold engine. It leaves the tappets sounding like a castanet player having an epileptic fit after a cold start and puts unnecessary strain on the oil pump.

2 stroke oil in use nowadays is almost all fully synthetic because it produces much less ash/soot deposits than mineral oil. My thinking is that synthetic 4 stroke oil will result in a cleaner engine for the same reason.

I'm willing to accept that I may be totally wrong but the same people who religiously advocate 10w40 semi-synth also seem to spend their weekends unblocking engine breathers, fixing noisy tappets and diagnosing terminal engine failures that seem to be caused by lubrication failure :(

The clincher for me is that last time I changed the oil VX were running a 'buy 3 get 1 free' offer which meant 4x 5 litres of 5w30 for £50 using my ABS membership :y
No problem to use the synth, but don't get swayed by the longer service interval.  I'm a big believer in using a cheaper, though still good quality, oil, but changing more regular.

OK, so I have an issue that may or may not be related to some engine work, but I am still more comfortable with fresh semi every 3k than I am with synth every 5k.  Those in the know that have been in the bowels on my engine have commented on it cleanliness.  Additionally, although I go through the motions, that car have only suffered breather issues when I first got it.


Some oils, Castrol spring to mind, just does not suit that engine - look at any Castrol filled Omega and notice the breathers are all mayo'd up...



As I have no plans to change from my 3k oil changes on any of the cars or the bike (annually - I don't do 3k in a year  :-[), I am content to stick to GM's semi synth.  The lawnmower doesn't care what it has, so that can stick on an annual dollop of GM semi as well ;D
Title: Re: Correct engine oil for 2.5 V6?
Post by: Andy H on 14 May 2010, 14:45:56
Quote
Quote
I switched to using 5w30 fully synthetic a few years ago because 10w40 is just too thick in a cold engine. It leaves the tappets sounding like a castanet player having an epileptic fit after a cold start and puts unnecessary strain on the oil pump.

2 stroke oil in use nowadays is almost all fully synthetic because it produces much less ash/soot deposits than mineral oil. My thinking is that synthetic 4 stroke oil will result in a cleaner engine for the same reason.

I'm willing to accept that I may be totally wrong but the same people who religiously advocate 10w40 semi-synth also seem to spend their weekends unblocking engine breathers, fixing noisy tappets and diagnosing terminal engine failures that seem to be caused by lubrication failure :(

The clincher for me is that last time I changed the oil VX were running a 'buy 3 get 1 free' offer which meant 4x 5 litres of 5w30 for £50 using my ABS membership :y
No problem to use the synth, but don't get swayed by the longer service interval.  I'm a big believer in using a cheaper, though still good quality, oil, but changing more regular.

OK, so I have an issue that may or may not be related to some engine work, but I am still more comfortable with fresh semi every 3k than I am with synth every 5k.  Those in the know that have been in the bowels on my engine have commented on it cleanliness.  Additionally, although I go through the motions, that car have only suffered breather issues when I first got it.


Some oils, Castrol spring to mind, just does not suit that engine - look at any Castrol filled Omega and notice the breathers are all mayo'd up...



As I have no plans to change from my 3k oil changes on any of the cars or the bike (annually - I don't do 3k in a year  :-[), I am content to stick to GM's semi synth.  The lawnmower doesn't care what it has, so that can stick on an annual dollop of GM semi as well ;D
I agree with pretty much everything above. I hadn't realised that 3k was a years motoring though. If an engine is left standing with old oil in it then I understand it can be quite corrosive so changing at least once a year is a good idea....

I seem to be looking at around 20,000 mostly motorway miles this year. 3k oil changes just aren't going to happen.....
Title: Re: Correct engine oil for 2.5 V6?
Post by: TheBoy on 14 May 2010, 15:04:29
Quote
Quote
Quote
I switched to using 5w30 fully synthetic a few years ago because 10w40 is just too thick in a cold engine. It leaves the tappets sounding like a castanet player having an epileptic fit after a cold start and puts unnecessary strain on the oil pump.

2 stroke oil in use nowadays is almost all fully synthetic because it produces much less ash/soot deposits than mineral oil. My thinking is that synthetic 4 stroke oil will result in a cleaner engine for the same reason.

I'm willing to accept that I may be totally wrong but the same people who religiously advocate 10w40 semi-synth also seem to spend their weekends unblocking engine breathers, fixing noisy tappets and diagnosing terminal engine failures that seem to be caused by lubrication failure :(

The clincher for me is that last time I changed the oil VX were running a 'buy 3 get 1 free' offer which meant 4x 5 litres of 5w30 for £50 using my ABS membership :y
No problem to use the synth, but don't get swayed by the longer service interval.  I'm a big believer in using a cheaper, though still good quality, oil, but changing more regular.

OK, so I have an issue that may or may not be related to some engine work, but I am still more comfortable with fresh semi every 3k than I am with synth every 5k.  Those in the know that have been in the bowels on my engine have commented on it cleanliness.  Additionally, although I go through the motions, that car have only suffered breather issues when I first got it.


Some oils, Castrol spring to mind, just does not suit that engine - look at any Castrol filled Omega and notice the breathers are all mayo'd up...



As I have no plans to change from my 3k oil changes on any of the cars or the bike (annually - I don't do 3k in a year  :-[), I am content to stick to GM's semi synth.  The lawnmower doesn't care what it has, so that can stick on an annual dollop of GM semi as well ;D
I agree with pretty much everything above. I hadn't realised that 3k was a years motoring though. If an engine is left standing with old oil in it then I understand it can be quite corrosive so changing at least once a year is a good idea....

I seem to be looking at around 20,000 mostly motorway miles this year. 3k oil changes just aren't going to happen.....
Sorry, to clarify, I meant the bike does less than 3k.  The cars do loads more...
Title: Re: Correct engine oil for 2.5 V6?
Post by: Greenbay packer on 14 May 2010, 16:31:09
Quote
Apparently VX are still running the 4 for 3 offer.

5W30 dexos2, 5 litre part number 93165557
Offer price for four cans £50.10
Equivalent to £2.51/litre

10W40 Semi synthetic, 5 litre part number 93165216
Offer price for four cans £32.67       
Equivalent to £1.63/litre

Are these prices with the ABS discount?  What percentage reduction do you get with membership?  I think on balance I'll stick to the semi synth (for this oil change at least), but £32 for four cans is pretty good. 

I also need to clean my breathers due to the mayo issue - I've see the guide on this forum, but was wondering if this could be done without removing the plenum.  With the scuttle off and the bolt under the ecotec cover removed, will the breather (I'm assuming this black plastic box that the pipes connect to is the breather!) not lift out, or am I missing something? 
Title: Re: Correct engine oil for 2.5 V6?
Post by: Greenbay packer on 14 May 2010, 16:36:57
Quote
Not all interested in the sports side of things ........

Just amazed at the headwear the fans wear! Why?

Dare you to post a picture .............

Why go around with a big wedge of cheese on your head... good question?  The area of Wisconsin around Green Bay produces a lot of cheese, but is that sufficient justification for wearing it?  It also produces a huge amount of sauerkraut, so I guess the cheese is preferable.