Hi everyone, I just wanted to introduce myself before I started asking questions about this truck I know virtually nothing about.

I'm being gifted a 2002 Ford Ranger XLT xcab 4x2 with the 4.0 and 5 speed auto and included the SLP Stage III Thunderbolt package, so it has an upgraded intake, headers, and dual exhaust. I had been in the market for a Ranger to use as a daily driver and hauler, so that I could spend time and money working on my other car, a 2008 Mitsubishi Eclipse that I've owned for the last six years.

While my plan was to drive the truck every day and upgrade the car to make it an 1/8 mile dragster, the reality is, the truck needs a lot more work than the car. I've kept the car maintained, it has 65k on it, and still starts runs and drives like a strong healthy car with a big *** V6 and enough horsepower to break traction in 3rd gear. The truck on the other hand, has 180,000 miles, the timing chain death rattle, and the transmission clunks hard when downshifting to 1st gear while coming to a stop. It also feels well down on power, rolling into the gas pedal doesn't make the truck behave with any particular urgency. My daily drive is better than 20 miles each way, and I'm pretty sure that if I put the truck to that kind of work duty that I'll kill it within a month's worth of drives.

I have to either keep the truck or refuse to accept it so I can't take it, sell it, and buy a better one, it belonged to my father and I told him I'd take care of it because he loves it enough to not sell but also can't afford the kinds of repairs it needs. Basically, I've decided that the truck needs to be my project vehicle, and I need to move the Eclipse on to someone else and get a different daily driver.

When I get the truck, the first thing I want to do is get the drivetrain sorted out, but I really don't know where I want to go with this. All my experience wrenching has been on FWD cars, and that work consists of maintanence and bolt-ons. One way or another, the engine on this truck needs to be pulled to address the timing chains, and the fact that it's generally anemic implies that I'm probably going to see something I don't like during compression testing. Drivetrain swaps are well out of my realm of knowledge so I'm looking for good guidance and writeups that can help me decide if I should stick with another 4.0 or if I can drop one of the V8s in without metal fabrication or custom wiring.

I appreciate any direction towards good resources that can help me, including here on these forums. I'm not looking for someone to tell me what I should do, just information to help me understand the options I have that won't break my back or the bank.

 

Welcome to the forum

You have a 4.0l SOHC engine in a 2002 Ranger, 1990-2000 Rangers used the 4.0l OHV engine, 2001 and up got the 4.0l SOHC engines

4.0l SOHC was first used in 1997 Explorers, and by 2000 the timing chain issue started to be acknowledged by Ford
It was not a 100% failure rate, but got up to about 25%
It was found that the 2 long chain tensioner's internal springs were failing
These are hydraulic tensioners but need the springs for startup(same as hydraulic lifters) before oil pressure got high enough

When a spring failed the timing chain would bang on its guide at startup, startup rattle, hardly noticeable because of other startup noises
Over time this would break that guide, and the rattle would come at other RPMs not just startup, so noticeable
Damage done

Ford redesigned the tensioners and put them in the supply chain around 2002, so 2002 engines assemble at the 4.0l SOHC engine plants should have the newer tensioners, these were shipped out to the Ranger assembly plants for the 2003 models, but they would install the previous years engines FIRST before using the ones that just came in
So 2003 Rangers may or may not have the newer tensioners, 2004 would have the newer tensioners

Up to you on swapping or repairing the current 4.0l SOHC
Swapping has the advantage of getting a lower mile engine and you can get the engine shipped and do the swap in a day or two
Repairing the current engine means pulling it and then installing the parts, and then putting it back in, so would probably take a few days longer, but its YOUR engine, a used engine is a roll of the dice as far as "other issues", you have no "reliable" history on a used engine, one of "the devil you know" choices, lol
If you get a used engine then I would FOR SURE replace the 2 long chain tensioners before installing, only use Motorcraft tensioners for this, the chains and guides can be 3rd party, but not the tensioners

4.0l SOHC is rated at 207HP, the Explorer V8 is rated at 215HP, so not really worth the swap cost unless you want to build up the V8 for higher HP
If you had a Blown engine and trans then it might be worth while, "there is no replacement for displacement"
You need to buy a 1996-2001 Explorer with V8, and 2wd if possible, and swap over drive train and computer with engine wiring harness, most years are well documented as far as wiring connections needed for the interface, but that is custom wiring
No welding or fabrication, parts are off the shelf or on the Explorer, which is why you buy the whole vehicle for the swap


You have a 5R55E automatic transmission, its not a bad transmission but does need to be serviced, generally speaking you can expect 250-300k miles on clutches and bands if serviced, some trans issues can be solved with new or rebuilt valve body, which can be done without pulling the transmission
Best practice would be to drain the fluid and look for debris in the fluid and pan, if there are metal bits then rebuild is needed, if not redoing the valve body should solve most issues, and not a waste of money since a new/rebuilt one is needed for a rebuild in any case

Used automatics are more of a roll of the dice than used engines, lol, but pretty simple swap
You would need a 5R55E from a 2001 - 2011 4.0l SOHC 2WD Ranger or Mazda B4000, the Mazda was build in Ranger assembly plants with same drive trains, B4000 = 4.0l engine
Transmissions from other engine sizes are 5R44E so won't work or bolt to your 4.0l SOHC
5R55E was change a bit for 2001 so earlier models from the 4.0l OHV or SOHC(Explorer) won't work either

 

Not trying to hijack the thread, but what did they change about the 2001 5r vs the older version?

 

2001 and up 5R55Es and 5R44Es got an added sensor, ISS sensor just above the shifter on drivers side, the 2001 and up computer needs to "see" this sensor on startup but also "needs" this sensor for shifting
2000 and earlier computers and transmissions didn't have or "need" this sensor, ISS = intermediate shaft speed in this case, there is Input shaft speed sensor as well, but its internal, its called TSS sensor, turbine shaft speed sensor

 

could you use a newer 5r in an older truck?

sorry Ron I forgot you already explained this to me, my dumb az didn’t look at the username

 

Yes, same wiring back to 1995, but not on 1994 and older, they used A4LD back to 1985/6 and C4 before that

A 5R will run the same as a 4R so you don't get the "5th" gear, which was actually a "2nd" gear between the old 1st and 2nd, but it will work just fine, same as 4R shifting
The 4R and 5R difference was in the Computer(PCM) software, it added the faux 2nd gear

One problem is that 1998 and up transmissions don't have speedometer output, so when using newer trans on 1995-1997 that presents a problem
The speed gear is still on the output shaft(2WD) but the hole to mount speedo gear is filled in, you can drill it out or you can used your older tail shaft housing with the hole
1998-2000 Rangers don't have that issue since speed was done using rear axle ABS sensor and GEM module