1996 Explorer 4.0 in 1999 Ranger?

[Z_Hrowal]

I've currently got a 1999 Ranger 4x4 with the 4.0 v6 in it. The truck just rolled 300k miles and is starting to show its age. Multiple oil leaks, severely down on power, and I just started noticing oil in the coolant. I'm not one to do anything halfway so i'm planning a complete overhaul for this truck, just did the same with the transmission about 70k miles ago. I've currently got 2 options and need some input.

First option is just to pull the current motor and do the full rebuild on it. Downside here is the amount of downtime. Due to having to order parts, wait on machine shop, and just nature of the project, the truck would end up being taken apart for probably 4-6 weeks, just basing on how similar projects have gone for me in the past.

Option #2 is to pick up a used motor I found from a 1996 explorer to use as a core to rebuild, then just swap the motors in a weekend. The motor I found is still running and he only wants $200 for it. Not to concerned about mileage as its gonna be completely overhauled. My only concern is the changes that were made over the years from 1996-1999. My main concern would be going from the 8 bolt crank in my truck now to the 6 bolt of the 1996. Second concern would be switching from the 98TM heads to the 95TM.

Are either of these things a major cause for concern? I've heard the 6 bolt cranks were also heavier, and I already feel like this truck is underpowered as it is so i'd hate to be taking steps backwards. Also, i've heard that putting pistons from a 90-94 4.0 can bump compression slightly? Is this something worth exploring or is it negligible?
Thanks

 

[bobbywalter]

i assume you have an OHV?

the 4.0 is about the most complicated engine ford has, in regards to constant revision and ease of mismatching parts and operating systems to the point of failure.

i would find a 99 engine to rebuild.

4 to 6 weeks in my world is how long you will have to wait for them to get to your engine to take 2-4 weeks to do the block heads and crank....with balancing..


doing this at least you know what you are getting for the money.

a fresh long block runs about 2500 or so on the open market last i checked. a co-worker of mine did not want a junkyard engine because they are all so old and high mileage.

bought a reman....it ate bearings in hours. not catastrophic and was running but lost 25 psi and was clunkin.... was down 3 more weeks while they sorted it out. got another reman and it has a rolling lifter tick.


so. its a tough call.


either way, mis matching parts even from a reputable reman place or a machine shop is something you have to be vigilant about.

valve seats have been a constant issue as well with crap parts being the rule these days.

it all depends on what is available to you.

 

[Z_Hrowal]

i assume you have an OHV?

the 4.0 is about the most complicated engine ford has, in regards to constant revision and ease of mismatching parts and operating systems to the point of failure.

i would find a 99 engine to rebuild.

4 to 6 weeks in my world is how long you will have to wait for them to get to your engine to take 2-4 weeks to do the block heads and crank....with balancing..


doing this at least you know what you are getting for the money.

a fresh long block runs about 2500 or so on the open market last i checked. a co-worker of mine did not want a junkyard engine because they are all so old and high mileage.

bought a reman....it ate bearings in hours. not catastrophic and was running but lost 25 psi and was clunkin.... was down 3 more weeks while they sorted it out. got another reman and it has a rolling lifter tick.


so. its a tough call.


either way, mis matching parts even from a reputable reman place or a machine shop is something you have to be vigilant about.

valve seats have been a constant issue as well with crap parts being the rule these days.

it all depends on what is available to you.

Yes, it’s the OHV. You’re kind of confirming my concerns here. Last thing I want is to get a used motor machined and assembled just to find out it isn’t even gonna work. Probably leaning towards just rebuilding what’s in the truck then…

I do have a good friend that runs a machine shop with his dad, they mostly do performance builds but he said they could take care of me, so lead time on the machine work shouldn’t be too bad as long as I can get it scheduled with him. Not a big fan of going the reman route. Probably ends up being a little more in the long run, and im not sure of the quality of work or parts used. Much more comfortable having everything machined and assembling myself. Quality parts for a rebuild are becoming harder to find as well. Rock auto has a lot of Engine Tech parts, which ive heard mostly good things about. Does anyone here have experience with that brand? I’d prefer to go Melling or Sealed Power for the parts I can but not everything is available through them