N62 4.8 Oil Thermostat Gasket Leak (2007 X5)

[bdcanetti]

Started off as a very slow oil leak (about a quart a month for 2 months) from an unknown location. Saturday it let loose and I had oil spewing from the drivers side front of the engine area. Local shop said he didn't want to touch it, dealer said between $2000 - $3000 job if it was indeed the gasket. So I tackled it myself. First off, I have been working on my own cars for 24 years and this was the most difficult job yet. Rate it a 8 out of 10 in difficulty for an experienced DIYer. Everything I found online was for the N62 or E70 WITHOUT the oil cooler thermostat. At least what I found gave me a general idea. I didn't have the time or patience to do a step by step but in short, here's what I did.

DISCONNECT BATTERY
1. Remove intake ducting and various snap off plastic parts.
2. Remove electric fan.
3. Drain power steering system, cooling and oil system.
4. Remove coolant expansion tank.
5. Remove alternator
6. Loosen Power steering pump and move to the side but leave hoses connected. This was horrible. Had to raise engine a few inches to make room to get it out.
7. May not be necessary but I removed water pump (which means you have to remove harmonic balancer and all belts) to make more room.
8. Disconnect two oil cooler quick disconnect lines top drivers side of engine compartment.
9. Remove drivers side front wheel and front half of wheel well cover.
10. Remove oil cooler thermostat. (2) Etorx E-10 bolts and (1) E-12 bolt. This was the worst. No room in there even if you get a ratchet setup on there. I suggest seeing if they sell Etorx box end wrenches. Would have come in handy.
11. Replace crappy $6 dollar seal, put it all back together, replace all the drained fluids and pray it all works ok.

Mine worked and spent about 21 hours of labor with my Dad helping. One hitch, I have a small vibration coming from the engine I can feel in the steering wheel and changes with RPM. I suspect the reuse and improper torque of the 8 torx bolts when I reinstalled the harmonic balancer. More to follow on that but open to suggestions from anyone that may sound familiar to.