Forum Discussion
carringb
Apr 26, 2014Explorer
The diesel isn't magic, it only gets slightly better economy than the V10. I would plan on 10 MPG and if you end up getting 11-12 consider it a good day!
Keep in mind it does not have ear the HP of the V10 (esp '00+ V10s) so while it won't sound like its working as hard, you don't be able to climb grades as fast.
Here some other notes I just posted on a van forum this morning when somebody else was asking about the same motor:
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Really, as long as its been maintained well, the 7.3L can go a LONG time. One thing to verify is that service included "Supplemental Coolant Additive". This is pretty important. Without it, it can develop pinhole coolant leaks into the cylinders from acoustic cavitation. If its had regular service at a diesel shop, probably nothing to worry about. If you find a small bottle of coolant test strips in the van, that means whoever maintained it on their own probably knows what they are doing.
Other than that.... The glow plugs don't last forever. They are cheap but a PITA to replace.
Fuel Bowl o-rings like to leak. Again, cheap fix and this one isn't near as hard. They tend to leak out of a lot of places. If it still leaks after replacing the fuel o-rings, throw in a couple bottles a Bars-Leak Engine Main seal repair, and call it a day. That stuff works pretty good.
The big problem is the transmission.... Behind the 7.3L it will go out. The torque converter simply wasn't matched well, and the lockup strategy makes the problem even worse because it spends excessive time unlocked (there are programming fixes for this, or you can install a manual switch). If you plan for a replacement when you get the van, worst case you won't be surprised when it goes, and best can you have 3-Gs sitting in your saving earning some interest. A larger cooler will also help a lot, but the torque converter strategy seems to be the root cause for the excess heat.
Ford offers a 4R100-HD reman unit. I don't think it costs much more for that unit, and should hold up much better.
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Hope that helps!
Keep in mind it does not have ear the HP of the V10 (esp '00+ V10s) so while it won't sound like its working as hard, you don't be able to climb grades as fast.
Here some other notes I just posted on a van forum this morning when somebody else was asking about the same motor:
-----
Really, as long as its been maintained well, the 7.3L can go a LONG time. One thing to verify is that service included "Supplemental Coolant Additive". This is pretty important. Without it, it can develop pinhole coolant leaks into the cylinders from acoustic cavitation. If its had regular service at a diesel shop, probably nothing to worry about. If you find a small bottle of coolant test strips in the van, that means whoever maintained it on their own probably knows what they are doing.
Other than that.... The glow plugs don't last forever. They are cheap but a PITA to replace.
Fuel Bowl o-rings like to leak. Again, cheap fix and this one isn't near as hard. They tend to leak out of a lot of places. If it still leaks after replacing the fuel o-rings, throw in a couple bottles a Bars-Leak Engine Main seal repair, and call it a day. That stuff works pretty good.
The big problem is the transmission.... Behind the 7.3L it will go out. The torque converter simply wasn't matched well, and the lockup strategy makes the problem even worse because it spends excessive time unlocked (there are programming fixes for this, or you can install a manual switch). If you plan for a replacement when you get the van, worst case you won't be surprised when it goes, and best can you have 3-Gs sitting in your saving earning some interest. A larger cooler will also help a lot, but the torque converter strategy seems to be the root cause for the excess heat.
Ford offers a 4R100-HD reman unit. I don't think it costs much more for that unit, and should hold up much better.
------
Hope that helps!
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