Is this bad news?

xc901979 · Post by **xc901979** » 04 Jul 2017, 01:09

Greetings, I am proud to say this is my first post guys. I recently swapped a blown xc90 2006 4.4 engine for a 2007 xc90 4.4 engine with 70,000 miles quoted by the mechanic. I want to repair everything that I'm able to on this xc90 on my own with the help from my new family. First, do I need the 2007 ecm module, or can I use the 2006 ecm module? Today, I found two leaks one at the rear differential and the other by the transmission / bevel gear. images below.

Post by **ggleavitt** » 05 Jul 2017, 10:22

Could check your power steering pump, see if it's leaking. While the PS pump leak may not be the culprit for your front prop shaft staining, it may well be the cause for your lower pan drops (get a white paper towel and see if the fluid is greenish in color (PS fluid) versus brown (oil). The PS fluid on a V8 has a tendency to run through the bottom of the "V" and appear as a leak towards the back or drivers side of the engine. This is one area to consider in your search.

Another cause for oil (if you determine that it is indeed oil that's leaking) on the bottom of the engine pan may be due to seeping valve cover gaskets, especially the back bank. Shine a light all around the rear bank gasket interface and see if it's leaking or has any seepage to speak of. Use a mirror if possible and check the entirety of the back bank towards the firewall.

I'm suspecting one or both of these is possible, please have a look and let us know. Thanks

traudesa · Post by **traudesa** » 07 Jul 2017, 14:53

As long as it's not making noise, that grease on your driveshaft doesn't look like a showstopper. You'll want to look into replacing the CV joint as some point, though. How does the front one look? Colorado Drive Shaft will sell you a kit to replace the joint for around $100 each, but if the middle one is leaking or the middle support is starting to make noise a new driveshaft may be the way to go. I replaced mine for about $500 since the front joint was completely blown out and the middle and rear were also starting to look kind of greasy.

Post by **precopster** » 07 Jul 2017, 17:09

Stick with the same ECM of you want it to start.

Post by **FLXC90** » 08 Jul 2017, 22:12

+1 on ECM, you are just swapping mechanicals, not electronics. When they do heart transplants, they don't take the brains too!

finding41 · Post by **finding41** » 19 Jul 2017, 07:27

The rear diff leak is probably just the main seal. The driveshaft will throw oil along way.
I'm sure there is a video on YouTube on how to replace those seals. Probably by this guy. https://youtube.com/user/volvosweden?feature=hovercard
If you don't have a good set of Torx and Allen sockets get one. Get a good set with a lifetime warranty. You are likely to break one trying to take something apart. (I have twice.)
I agree with the above guys about keeping your electronics. Only swap mechanical parts with a Volvo or you are in for a trip to the dealer to have the electronic parts "married" to the car.
Good luck.
Marty