This is my story guys, I bought an 02 disco with 74kmi for a song and a dance because it was siting up for a few years. Turns out all it needed was a fuel pump and a lot of cleaning since it was used for a hunting camp truck. My wife loves the truck because of the height and room but was not happy with the condition of the exterior and interior. We came across an 03 while on a quest to find a donor vehicle so we bought it since it was in great shape cosmetically but turned out to be a dud with a bad engine. I thought no biggie, i'll just take this great running engine from the 02 and sell it for parts after. was my reaction when i find out they would not interchange. I worked as a mechanic for many years but never on Land Rovers but nevertheless, i tackled the head gaskets however the vehicle still overheats due to compression gaskets leaking into cooling system. I researched and came to the conclusion i have a cylinder liner problem. I want to fix it but not sure whether to spend $ 2,800 on a used low mileage engine, rebuild myself with flanged cylinder sleeves which will run about 3-3.5K to do or just buy an allready rebuilt engine which from what i have seen runs about $5k and thats pushing the limit on what i want to spend unless i sacrifice the 02 for repair funds. Please guide me along the right path. Thanks

 

No need too
I believe the 4.0 in your 2002 is the same as the 4.6 in the 03 the exception being the stroke.
So you can put the 4.0 into the 03 just use the short block with the 4.6 secondary air heads.
It will have a little less ***** that’s all, or swap the crank into the 4.0 block to have a 4.6.

 

Probably the ECU has a different chip in it for the 4.6 fuel map too.
Or a different program flashed into it.
Not sure if a Testbook can flash an ECU.

Easier to swap ECU's.

 

My main question is to rebuild or replace. If i replace engine with reman, which company should i consider. If i rebuild, where is a good source for rebuild components?

 

For what it is worth, you do not need to change the ECU, but you can have it programed fore either engine with the help of a high end scanner.

 

I would get a good 4.0 block and rebuild it.
The 4.6 block in 2003 seems to have more sleeve issues.
Not sure about 2004.

So, a 1999, 2000, 2001, 2002 block would work for you.
I would go to a junk yard and have them start it and make sure it at least sounds good.
But you will not know really if the block is good until you have hours of running time.
There is no way to know until you get to know the engine.
It is a crap shoot.

Unless you get a good rebuilt engine with a known good block.

JE Robison Service — the blog: The last word on Land Rover liner failures - I hope!

 

for $3 grand i would just buy another one and have the 03 as a parts truck.

 

Buying one for parts is how i ended up with two rovers and i think for $3k any disco would be a high mileage vehicle or one with issues. Just not sure i want to take on another project like that.

 

If i remember correctly, dosent the 4.0 have a different oil filter mount compared to the 03 4.6?

 

you have a good running but dirty 02, and a dud 03, correct? either sell them both and buy yourself a nice 04 that has fresh head gaskets. or sell the 03 for parts and scrap and buy your wife another d2 that is in good condition. there are so many up here i cant count.