2004 XC90 T6 Engine swap?

GonzoGirl5 · Post by **GonzoGirl5** » 12 Aug 2020, 13:30

OK, after much debate and many suggestions I just can't give up my XC90 T6. The head is blown for sure. Since there are so many issues with the T6 engine I am wondering what Volvo engine I could swap out with. Is there an engine that I would be able to just drop it in. It is an AWD twin turbo of course being the T6. If I would have known I would have bought a different model but now that I am a new transmission, $700 all terrain tires and a million other things into it I do not want to just let it go. I would consider just replacing with the same engine but I feel at this point that it is not a wise decision to do so considering everything I have learned. So, what engine could I match to just simply swap out with? Any suggestions are very much welcome. Thanks.

Post by **June** » 12 Aug 2020, 21:07

As far as I know the T6 engine is sound! It's the transmission and AWD which had failure problems. A good complete used engine should be cheap compared to a hpt 2.3 R engine I would think. Have you checked used engine prices? June

Post by **SuperHerman** » 12 Aug 2020, 21:38

Without changing all sorts of electronics, harnesses, modules, transmission and drivetrain ... your only option is another 2.9T. Realistically that is your only choice.

The 2.9 is a great engine. Why did yours overheat and can you just replace the head gasket? I did a head on a 2.9 non-turbo on a 2004 S80 and it was not a bad job at all. Typical Volvo design and procedure so if you are familiar with the 2.3/4/5 variants the 2.9 is much the same.

Post by **RickHaleParker** » 14 Aug 2020, 16:04

All the white blocks are the same technology and design. They are called modular engines for a reason.

GonzoGirl5 · Post by **GonzoGirl5** » 15 Aug 2020, 20:01

June wrote: ↑12 Aug 2020, 21:07 As far as I know the T6 engine is sound! It's the transmission and AWD which had failure problems. A good complete used engine should be cheap compared to a hpt 2.3 R engine I would think. Have you checked used engine prices? June

I have checked into used engine prices. I guess, I just am a little gun shy at this point. I have replaced the transmission and is still under warranty. I suppose I should look into just swapping it out.

GonzoGirl5 · Post by **GonzoGirl5** » 15 Aug 2020, 20:02

SuperHerman wrote: ↑12 Aug 2020, 21:38 Without changing all sorts of electronics, harnesses, modules, transmission and drivetrain ... your only option is another 2.9T. Realistically that is your only choice.

The 2.9 is a great engine. Why did yours overheat and can you just replace the head gasket? I did a head on a 2.9 non-turbo on a 2004 S80 and it was not a bad job at all. Typical Volvo design and procedure so if you are familiar with the 2.3/4/5 variants the 2.9 is much the same.

Yeah, I can replace just the head gasket, I was more just wondering if it would be worth it to put a different engine in it, I love the car and would hate to see it go. Especially with a new transmission. I would love to have a donor car. One with a good engine and a blown transmission for cheap.

Post by **RickHaleParker** » 16 Aug 2020, 07:31

GonzoGirl5 wrote: ↑15 Aug 2020, 20:02 Yeah, I can replace just the head gasket, I was more just wondering if it would be worth it to put a different engine in it, I love the car and would hate to see it go. Especially with a new transmission. I would love to have a donor car. One with a good engine and a blown transmission for cheap.

The lower end on these engines are almost bulletproof. You don't replace them unless something went wrong in the lower end.

1. Rebuild head.
2. Service PCV.
3. Set of remanufufactured injectors.
4. Plugs.

Then it should run as good as new. Better way to go then a used engine.

Post by **June** » 16 Aug 2020, 08:22

You still have had coolant in the oil for two months now. My choice would be a used engine. June

Post by **RickHaleParker** » 16 Aug 2020, 11:11

June wrote: ↑16 Aug 2020, 08:22 You still have had coolant in the oil for two months now. My choice would be a used engine. June

Good catch.

She would need a B6294T out of a 2002 - 2006 XC90 T6 or S80 T6.

A B6284T out of a 1999 –2002 Volvo S80 T6 would work also. Would lose 139 CC of displacement but it is a direct drop in replacement.

The NA 2.9L are to high of compression for the twin turbos.

Post by **SuperHerman** » 17 Aug 2020, 23:48

I am not so concerned with coolant in the oil - coolant prevents rust. I am more concerned with why it blew the head gasket and how long it was run in said condition. Coolant is not a lubricant like oil and if it ran too long it can destroy the pistons, rings and/or cylinder walls. One only knows when the head is pulled and the block can be inspected.

I have done several head gaskets with milkshake oil without any issues. I have done one, a 2004 S80 2.9, that was driven too long with the milk shake mix (how I bought it) where I had to replace one set of piston rings and hone one cylinder wall. It came out fine.

If you plan on doing it yourself and do not have a lift and/or proper space the head gasket is easier. If you are going to have someone do it, a used engine will come out cheaper.