i have a 99 T5, and it seems like it goes through oil quite quickly, i filled it about 2 weeks ago and its already down a third. is this normal for this model or do i have some problem car? im not noticing any leaks on the garage floor. thanks.

1980 MB240D started using oil (1 litre/2000Km) @ about 200,000Km. Switched to
0-30 semi-syn for winter (from 15-40 diesel) and my consumption dropped to no add between changes @ 8000Km. Switched to full syn and use 1 litre between changes, but now have 400,000km. Boat diesel wore out, used 1 litre/ 6 hours, switched to synthetic and used 1 litre / 30 hours. 1997 855 AWD 140000km and
1999 AWDR 85000km use nothing but syn. Also 3208 Cat in motorhome, 2000 prelude, 1998 MB C230... you get the idea

Hi,
Concerning synthetic oil, here's what a mechanic friend of mine showed me. If you were to drop let's say a wrench into a vat of used synthetic oil, you would notice that no drops of oil get splashed around, as opposed to mineral oil which does splash around. This means that the molecular structure of synthetic oil is such that its parts are all linked and react something like an elastic. Now, when you add synthetic to an engine that has reasonable mileage, without it being very high, the oil will find openings and seep out of areas around seals and gaskets, acting like penetrating oil and continuing to seep out because of that molecular structure (elastic), but you won't find any on the ground . I have verified this myself on another car and found it to be true. As soon as synthetic oil finds an area to leak out of (through which mineral oil doesn't), it then keeps seeping out. In a case like this, when you go back to mineral oil usage, there are no more leaks. I personally use semi-synthetic for the time being in a 98 s-70, and haven't noticed more consumption than with mineral oil. I will soon switch to full synthetic and keep an eye on the situation.
MHV

Was that 1/3 of a quart in 10 miles? 200 miles? 500 miles? 1000 miles?
What kind of oil are you using?
How many miles on the car?


Even in a new car, the manufacturer will tell you that a quart of oil every 700-800 miles is within acceptable usage.

Sounds like my situation. I also have a 99 T5 (bought used with 58,000 miles), and after switching to synthetic oil six months ago, have experienced oil loss. Most recently, I was down 5 dipstick hashes after about 2000 miles. No visible leaks on the ground either. I've taken it to the dealer twice: first time they replaced the dipstick seal. Second time they couldn't figure it out. The plugs are not fouled, no oil anywhere. Now I'm on a 1000 mile "oil consumptin test." Dealer tells me that according to Volvo, "normal" oil consumption is 7/10ths of a quart every 1000 miles. That simply astounds me. I had an 83 244 with 200,000 miles on it and it never leaked a drop.

I've read all the posts about switching to synthetic and I'm going to push for the seals to be replaced, but I'm concerned that they'll stonewall me. The dealer suggested switching back to dino oil because "synthetic oil burns more." I really don't want to do that. Anything you find out will be helpful.

Did you use an engine flush before changing to synthetic?
I don't know how much oil "five hashmarks" represents, but if the oil level was OK for a couple thousand, and then consumption jumped up, change the oil filter and top off.

I also have a 99 T-5, but have not experienced oil burnoff at anything close to the rate that you have experienced.