i put full synthetic 5w30 in & noticed oil leaking. should i try regular petro in maybe a 10w40 or even thicker oil? anyone ever use shell rotella 15w40 here? car has 154k mi. any comments/recommandations would be appreciated.

 

You could use a thicker non synthetic oil, but I think that's just putting a bandaid on the situation. I would try and pinpoint the leak fix that and leave the synthetic oil in... But that's just me.

 

what if its the rear seal? i know id have to pull the tranny & that would totally suck!

 

You can try this, http://www.barsproducts.com/1050.htm

But definitely try and see where the oil is coming from, it might be something really simple.

 

+1 on that, plus I have learned in my shot time in this planet that it's usually something stupid!

 

I would not use that. There is already problems with the oil passages in these cars usually from people not changing the oil enough and sludge building up. That stuff would make it worse.

 

I didnt know that. Ive never tried it, but I have heard good things about Bars leak so I figured I would throw that out there. Would you say the same thing about high mileage oil?

 

No I would not the high mileage oil should be fine.

 

I would just get it diagnosed and go from there. I know high mileage oils have conditioners for seals,etc..... I am a fan of just changing out stuff instead of trying to condition something that might be "too far south" as they say! Plus with age, it's to be expected that some stuff will be needed. But that's just me....

 

im almost positive its the rear seal. i wanna try one of those high mileage oils since they have the seal conditioners. how thick can i go and which should i go with synthetic or just regular petroleum?

 

OK more searching & I wanna try the "Auto-Rx Rotating Seal Leaks Application". This stuff looks pretty interesting.
*Can I buy this Auto-Rx at the local parts store or is it mail order only?
*What conventional oil should I use with it during the process (standard or high-mileage oil) & how heavy can I go since it's starting to get warm out here in NorCal?

 

As previously stated, it's probably a main seal leak that these vehicles have a tendency to do according to my independent Volvo dealer........we had to get our 1995 850's done when we still owned it and it was about $1000. The quick fit additives could harm your engine, especially if it's a turbo. If you've been using synthetic, why not stay with that but switch to the a high mileage one like Mobil 1 High Mileage 10-30 (not Extended Mileage).

 

wouldn't synthetic hi-mileage be more prone to leaking than the non synthetic hi-mileage oil? also, could i use something thick like 15w40 or 20w50 since weather is starting to get hot out here?

 

Anyone? Wow $1000 is quite a bit of cash

 

I know the high mileage Oils have conditioners for older motors. I used to run the Valvoline stuff on my 93 Honda Accord.. Those oils apparently help with seals and other parts in conditioning. It might be the main seal, it might not.... Is there a place that you go to for service that might be able to look at it. I'd hate to speculate that it's a grand and be something stupid! On the other hand it might be the main seal.... But we can go back and forth on this one. I'm not trying to discount anythign said by anyone but I think like dan2286 and my self have said, just have it looked at it..... If it ends up being something stupid,you will feel WAY better about yourself and not stress. If it's the main seal, then we can go from there.

 

I think the point of the high mileage synthetic is having the benefits of both types of oils. I have no idea if it works because as far as I know, it is a fairly new product. If it does what it says it does, you will have less engine wear and not have to worry about leaks getting worse, maybe leaks will even get better.