2005 XC90 Engine Swap

[Masscomguru]

No the 2.9 had a chain drive transfer case, the 2.5 has an angle gear.

[Batty251]

No the 2.9 had a chain drive transfer case, the 2.5 has an angle gear.

So from some images and research and quote me if i am wrong. The angle gear is bolted to the side of the transmission and the Haldex AWD system is the rear diff and basically the angle gear is connected to the drive shaft that sends the power down to the Haldex system for the rear diff and the engine is mounted with the transmission side ways in the engine bay because the 2.5T was originally FWD and AWD was a optional extra.

2.9T has the engine in side ways as well in the engine bay but the transmission replaces the angle gear that is used on the 5 speed. the drive shaft is connected into the transmission of the 2.9T and then sends the power down to the AWD system which is a chain driven system that sends power to both the rear and the front instead of the front being attached to the transmission.

[SuperHerman]

If I recall you are missing a part. There are three fluids up front so three different parts: transmission, angle gear/transfer case, chain drive system. Chain drive is on the far outside and then the angle gear/transfer case.

https://www.volvopartswebstore.com/show ... ct=1184103

[Batty251]

XC90 AWD System

The image is what i am going off by how the AWD is setup on the 2.5T.

I am just hoping i can still use the CV on the current setup to minimize costs.

[ggleavitt]

I'm sure the mechanical is do-able but in 2005 the CEM and REM physically change across the P2 line as does the error code structure which means new software so a 2004 engine management set (you're doing the ECM/TCM module and connection from the donor, right?) might not function properly in the 2005 network. This could be a good question for the European folks who know CANBUS as I believe that 2005 also marks a change in HS bus speed from 250kbps to 500kbps and that may well be hard coded firmware.

**I'll add fuel system compatibility to the mix, I wonder if the 2004 donor motor and ECM are set up for a demand fuel pump as I suspect are installed in your 2005. If not, you'll nee dot figure that out as well.

If you can find a copy of VIDA and get it loaded on a PC (search "VIDA 2014 image", it's free), I think you'll see what I mean. May well work and I'm happy to be wrong but I think the change in architecture that occurs between 2004 and 2005 model years may prove problematic.


Good luck.

5/16/20- edit ** Vehicle is not North American market, may not have DECOS.