How to change timing belt on 04 volvo xc90 2.9L engine

You mean the transmission fluid should be changed? Yes, every 60k miles or 100km, the transmission fluid should be drained and refilled. Dealership charges probably around US dollars $189.99. If you are talking about having the timing belt changed, then no, the mileage is still low enough and I bet that it is fine. You can pull back the plastic cover on the side of the engine and look at the timing belt yourself. It's actually very quite simple to do. If it looks black and not faded, it should be fine. BUT, if there are tiny cracks in it or the belt itself is starting to shred, CHANGE IT IMMEDIATELY! Hope this helps. Owners manual for Volvos say that the timing belt should be changed every 60k/100km, but Ive had Volvos all growing up and 99% of Volvo Mechanics say that the belts can go at least 100k/160km. My 2004 Volvo S60 2.5T AWD went 128,500 miles and 10 years before my Volvo Mechanic said it was time. It all depends on several different factors, but realistically, you probably will be fine for another 25km at least.

Here's a link to your code.

Well, most belt companies and aftermarket folks recommend 60,000 to 80,000 miles on a timing belt. You have an interference engine which means if the belt breaks while the engine is running it could damage the valves and pistons. So I would recommend doing it soon.

Volvo recommends for Volvo S80, changing the timing belt every 105,000 miles. Needless to say, they are pretty religious about this now.
The B20, B21, B23, and B230 engines are non-interference engines, meaning that the camshaft can be rotated independently of the crankshaft and no damage will result to the engine. That is, if the timing belt breaks, the valves will not hit the pistons; the engine will simply stop.
On the other hand, the B234 16-valve engines and any of the other Volvo multi valve engines are interference engines. Loss of the timing belt in these engines will result in severe or fatal engine damage.
Your car might be fitted with:
2.8L (VIN 90, 6th & 7th digit, B6284T eng, turbo)
2.9L (VIN 94, 6th & 7th digit, B6294S eng)
To get more information you can download the Owners manual at:
http://new.volvocars.com/ownersdocs/2001/2001_s80/01s80_08b.htm

Most car dealers recommend maintenance services at 30K, 60K, 90K and so on. The 30K service is mainly focused in inspection of the systems and replace of the fuel filter.
The 60K is expensive for cars with timing belt. The coolant, transmission oil and filter, and the brake fluid has to be changed. The air filter and spark plugs has to be replaced at this time too.
Most costly is the replacement of the timing belt. Volvo recommends for Volvo 240, changing the timing belt every 50,000 miles. Needless to say, they are pretty religious about this now.
The B20, B21, B23, and B230 engines are non-interference engines, meaning that the camshaft can be rotated independently of the crankshaft and no damage will result to the engine. That is, if the timing belt breaks, the valves will not hit the pistons; the engine will simply stop.
On the other hand, the B234 16-valve engines and any of the other Volvo multi valve engines are interference engines. Loss of the timing belt in these engines will result in severe or fatal engine damage.

You should have changed the Timing Belt at 60K niles, by not changing the Timing Belt you are taking a serious gamble on the Belt breaking on you at anytime, leaving you stranded and costing you thousands of dollars in engine repairs. If your car runs fine, No Check Engine Lights, I would just do your regular engine oil changes, flush Radiator, Change Transmission Fluid and Filter, but change the Timing Belt ASAP.

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Hallo Markmac945,

I've been a Volvo Service worker for about a year and seen lot of these Volvo's. It's true that if the timingsbelt snaps the engine wil be ruined. It would be wise (seen that the service history isn't there) to change the belt if your not sure it happend. I life in the Netherland and because we have cars with a KM-dile, i don't know if this is any help but; timings belts in Europe sould be changed at 120.000 KM. How manny miles that is, well I just don't know. The engine in your Volvo is an B21 or B23. Both timing belts have to be changed at 120.000KM. But for the price (being a easy timing belt change) I sure change the timing belt. Than you'll be sure that everything is in good order.

this claims to be for '04 to '06 aveo 1.6L engines, i don't know if it will cover other years
found this by chance as I need to change belt on wifes car BEFORE it does break
http://home.earthlink.net/~aveobot/id1.html

print it all if this is what you need, tells just about all you need to know.