2000 V70XC Switching from dino to Mobil 1: drain oil cooler?

v70XCSteve · Post by **v70XCSteve** » 02 Oct 2014, 09:59

I want to switch from the dino oil that the PO used to Mobil 1 High Mileage, but what about the oil in the oil cooler?
The specs for the car
( http://new.volvocars.com/ownersdocs/200 ... .htm#pg134 )
say that the oil capacity is 6.1 US qts, plus 0.95 qts " if the oil cooler has been drained ".

Seems like there is no way to really purge the oil without leaving 1qt in the oil cooler, so if you switch types, or use a flush like AutoRx, MMO, Amsoil, etc., then you'll never get it all out.

If there is almost a quart of oil in the oil cooler, and I change the other 6, is that just what you live with, or is there some way (a.k.a. easy way) to drain the oil cooler too, at least for the initial switch-over?

Post by **abscate** » 02 Oct 2014, 10:06

Don't sweat it, just let it mix and change out on next oil change. Add 5 Qts synthetic, idle, let drain down, top off to top of dipstick.

Did that to my 1999 last year, no issues

Post by **cn90** » 02 Oct 2014, 12:13

I asked myself the same question a few years ago.

If you are a purist, then drain the oil cooler, however, there is pitfall associated with that, search forum for troubles that can come with it (clip installed backward, or loose clips that need a clamp or zip tie to hold it in place etc.).

If you are practical, then do not drain the oil cooler. This is my approach as well as 99% of people in this forum.

Post by **regent** » 02 Oct 2014, 12:36

cn90 wrote:...If you are a purist...

I do not see anything wrong with the 'purist approach' - I'd take the whole engine apart, wipe off the dyno oil residue from each piece, and then rinse everything thoroughly in a solvent bath a few times... (to be somewhat 99.99% sure before putting everything back together)

Post by **abscate** » 02 Oct 2014, 12:46

What about the old oil aborbed into the first nano layers of the hoses? Shirley you would treat these with diatomaceous earth to make sure that didn't contaminate your new oil?

I moved 4 relatively high mileage (50-150k) cars from dino to full synthetic last year - against all the internet advice of seeping gaskets, oil burning, ring damage, and ebola risk. The only car that uses any oil actually had its consumption roughly halved. It sure is nice just having to buy one kind.

And, thank you for your excellent netiquette in starting a new thread on this!!

Post by **erikv11** » 02 Oct 2014, 15:48

In reply to the OP's actual question: You can very easily drain the oil cooler by just disconnecting the bottom hose where it connects to the radiator. People remove and reconnect that hose all the time, it is not rocket science or risky in any way or even difficult to put back on, but you have to pay attention. You can drain the hose itself this way, too. It will be messy, though.

As to whether or not that is necessary or advised, well you've got several good opinions on that one ...

Post by **abscate** » 02 Oct 2014, 15:55

I think from 1999 on the biscuit oil cooler on the right side of the engine is used (towards rear of car). I don't think it's as easy to drain as the cooler-in-radiator type

Post by **erikv11** » 02 Oct 2014, 17:45

Oops I failed to read the post title!

On a 2000 the "biscuit" type oil cooler is on the oil pan. I actually thought those will drain by gravity anyway, if you just wait. You could always unhook one of the hoses to be sure, they are pretty easy to access from under the car, although I have not looked at the underside of an AWD and there may be stuff (bevel gear, etc.) in the way.

On a FWD P80 car: