Sorry to hear about your Issues. Wish I was on this forum sooner to help you trouble shoot your LR3.
-From my research I believe the long block is the same engine in an LR3 as a ford ranger and explorer 4x4. It’s has to be a 4x4 v6 from a ford because it needs a balance shaft installed.
- Engine compression ration in the Land Rover Data shows 9.75:1 + or - .5 for the V6. Some literature even says 9.7:1.
- Ford lists all 4.0 sohc at 9.7:1
- Now as for the power output. Ford lists all the horse powers between 205-210hp on regular 87. Land Rover clams 216 hp on premium. Also the lr3 has dual factory exhaust which I believe is the exact same as the v8 as the catalyst are the same from after market part number cross examination. The lr3 v6 basically also has shorty, dual wall, stainless steel headers from the factory which most likely flow way better than the cast iron manifolds Ford installed on the 4.0. This all can explain the extra 6 hp easily along with a premium fuel tune.
- To explain the extra torque output of the LR3. I must say this is the one thing this engine does well. Basically all Ford 4.0 sohc engines are rated at 240 ft/lbs except those with either a active intake manifold, like the lr3 and 1997-98 explorer, or long runner intake, like the 2002-2009 explorer. With the better intake manifolds the Ford Explorer pumps out 254ft/[email protected]
3500 RPM. The lr3 with its beautifully designed aluminum active intake manifold puts out 269ft/lbs @ 3000 RPM. With one ignition coil per spark plug and premium fuel tune,which can advance the spark sooner, I think this accounts for the better torque output at lower RPM.
- I have repaired my 2008 lr3 a few time. Most parts fitted to the v6 are stamped Ford Mo Co. I have even used the map sensor off a junk yard 2006 Explorer sports track to fix mine. Same part number and all.
- I don’t think Land Rover had the budget to reengineer the 4.0 SOHC from Ford. If they had I’m sure it would be pushing out bigger numbers. The 4.0 is limited by its cylinder head air flow because it’s only 2 V per cylinder, this explains the great torque but how it runs out of breath by 4500 RPM. Land Rover would have to spend a great deal to improve the 4.0 sohc over its explorer roots and since this was to be a lower range engine I think they changed as much out side the long block as they could and strapped it to the sweet ZF 6 speed and called it a day.
- I plan to use a used or rebuilt ford engine when mine goes. I will compare all internal part numbers on the cams, heads and pistons but I’m 95% sure everything will be identical from all the research I have done.
- The timing components I believe are failing on these engines, especially on the LR3, because of long oil change intervals. The chain guides are not the best, especially on the passenger side, but if you keep up on your oil changes and use a great filter these engines will last a long time.
- My oil service reminds me every 12,000 km on my LR3 which I believe leads to the tentioners plugging up and then comes chain rattle on cold starts. Eventually causing timing chain guide failure. I only go 5000km on synthetic with an FL80 motorcraft filter in order to get the best life out of my 4.0 sohc.
I hope This research I have come across can help those with future problems.