98 V70 NA Synthetic oil change interval

Post by **98v70dad** » 19 Feb 2016, 18:10

I'm going to try out Mobil 1 all synthetic oil for older cars in 10W40. I had a problem with burning oil and switching to 10W40 instead of 10W30 helped a lot with that. I've never used synthetic in any of my cars and I'm wondering how often I should change it. 8000 miles seems about right but its just a guess. Any recommendations? Also if an oil filter stays in the car for twice as long are there any special considerations for choosing an oil filter? I usually buy Purolator filters for my 4000 mile interval I use with dino oil.

IG-88A · Post by **IG-88A** » 19 Feb 2016, 18:17

I usually buy Mann or OE Volvo filters for mine, after reading that they contain a check valve that prevents dry starts. I think there is another recommended brand out there, but I'm not sure what it is at the moment. I cant comment on the Purolator filters. I always try change my Mobil1 every 5000. But I have a friend who lets his go a bit longer. I've always used dino oil in my NA and synthetic in my turbo. But my NA is currently in need of lots of love. I may end up switching to synthetic in it before long. And I use 10w-40 in both of them. I'm sure many others will chime in with more experience than I.

Post by **98v70dad** » 19 Feb 2016, 18:40

I've read that the 98 v70 doesn't need the check valve. Purolator makes great filters for the price. My car is old enough and has had enough previous owners that I don't worry about the check valve issue. The people who owned it before me took it to Jiffy Lube. Any wear caused by using a non check valve filter already happened long before I got the car.

Filters collect dirt and its recommended that you change them at every oil change. If you use dino oil and change the oil and filter every 4000 miles and then switch to synthetic oil and change the oil and filter every 8000 miles its equivalent to changing the oil filter every other oil change with dino oil. In other words leaving in an oil filter for 8000 miles will mean it has twice as much dirt, twice as much pressure drop across the filter, etc. I've always wondered about this and you won't find much information about it. Longer intervals, same filter...doesn't make much sense to me.

I want to switch to synthetic oil so I won't need to do the PCV upgrade/cleanout again. I plan to keep the car for two more years and I think using synthetic oil will help with that. I also maintain three cars and I'm always doing oil changes. Doubling or tripling the change interval will free up some time for me.

Post by **cn90** » 19 Feb 2016, 19:20

8K maybe OK for new engine, but with a car this vintage with a lot of blow-by:
- Standard oil...3K-4k
- Synthetic oil...5K or so

It is not so much standard vs synthetic, it is the short trips (<7 miles in mild 30F temp) that damage the engine.

Good oil filters: Mann, Mahle OC-204, Bosch, Purolator.
Buy a whole bunch to save shipping cost.

I posted info re oil filters below:

https://www.matthewsvolvosite.com/forums ... hp?t=42989

Post by **stephansvolvo** » 19 Feb 2016, 20:59

when I rebuilt my engine almost a year ago I switched over to full synth 10-30, valvoline. I ran the first for 3k and the second change for 5k. I am on 6k on this one and I will be changing the oil this week as I can tell that was too long. I dont think in the future on this V70 GLT I will put more than 4k on it. I use only Mann as I order them from IPD in bulk. I have run the purolator but not anymore.

Just my .25 cents.

Stephan

Post by **rspi** » 20 Feb 2016, 04:49

I use my Blackstone lab info and the owners manual to guide my oil changes. I run full synthetic and change about every 8,000 on my turbo 850.

I believe the owners manual states 10,000 mile change intervals on the NA cars. With full synthetic you should be able to do at least that, probably more. Car manufacturers test the engines with the recommended oils. When the oil service additive package is near depletion, they mark that wear and recommend oil changes with that info in mind so you will change the oil within plenty of time to avoid engine wear. Remember, these cars have large sumps, more than 50% than many.

The turbo and NA cars have basically the same engine, the filter should be the same.

I guess you need to be prepared for about 60 more options.

crlande · Post by **crlande** » 20 Feb 2016, 05:20

From the manual of both the '94 NA and '98 Turbo:
If driving conditions include:
Extended periods of idling and/or low-speed operation
Frequent short trips less than 7 miles 11 km
Extended periods of driving in dusty and/or sandy areas
Trailer towing
Driving in mountainous areas
Then the correct oil/oil filter change interval is:
EVERY 5,000 miles= 8,000 km OR EVERY 6 MONTHS, WHICHEVER COMES FIRST

Primarily highway driving
Frequent trips of longer than 7 miles = 11 km
Then the correct oil/oil filter change interval is:
EVERY 10,000 miles = 16,000 km
5,000 miles= 8,000 km * OR EVERY 12 MONTHS, WHICH EVER COMES FIRST
* Turbo-charged models
++++++++++++
So the engineers want the turbo changed at 5000 no matter what type of driving.
The syn oil does not break down as fast as dino oil but it is still collecting dirt and combustion gases.

Post by **misha** » 20 Feb 2016, 07:54

What crlande said.^^^
Oil change interval is not depending just on mileage.It's also dependant on how the car is used.
Optimal time and mileage of oil replacement(synthetic or mineral) should be one year at MOST and around 10k km,whichever comes first.
For mostly highway driving it could be stretched to 15-20k km but also at one year interval so again....whichever comes first.
Oil filter (Mann,Knecht,Mahle or Bosch)must be replaced every time you change the oil and that's only regular oil replacement.

Post by **dosbricks** » 20 Feb 2016, 18:48

Does your V70 use a spin-on oil filter, or the drop in cartridge type? If the former, then the check valve is important.

80% of engine wear occurs in the first three seconds after cold startup if using a non-check valve oil filter. If you are not concerned about whether the filter has a check valve, then there is no need to be worried about running Mobil 1 high mileage 10w40 for 7-8k.

If Robert gets a clean lab report from Blackstone to 8k with full synthetic and the same filter, then it's good to go.

Post by **98v70dad** » 20 Feb 2016, 20:08

Everyone seems to have overlooked that the previous owner didn't take care of the car. I got it at ten years old and 100k miles. There is no point in doing the best thing when it's way too late for that. I just want to put two more years of almost all highway miles on it. I can look the ideal recommendations up. I'm interested in what you would do for 1500 dollar car.