Latest PCM Upgrade 1U7A-12A650-GMB for the 2002-2005 4.0L SOHC

[Drewmcg]

Question for you. For me as someone that is just getting into learning and repairing vehicles. How hard do you think valve covers on my explorer would be for a newby? I am comfortable do like breaks/starters and stuff like that but not 100% if i want to takle somthing like this by my self so early. I read around people say there a pain and they just took them to the shop to have them done . Some said it was not to bad. An input would be appreciated

You've left out some important info, so hard to advise. How many miles? Body in good shape? Any prior engine work done? And especially, any chain rattle on cold startup? Do you love your SUV?

Valve cover gaskets are not a trivial job for DIY on the 4.0 SOHC. It can be done with lots of research and patience (may take a couple of days all told). The big challenge is removing the plenum (plastic intake manifold). The star bolts holding down the plenum are real hard to get to, and could strip. Best to remove hood and use step stool to get the rear few bolts. Use 1/4 inch ratchet and variety of extensions, swivel joint. I even used a couple different profile star bits. And think trips to Ford dealer parts department for replacements, and waiting several days for new bolts.
Rock Auto for valve cover gaskets and new plenum gaskets. I've had better luck with the German ones than Felpro (which I generally prefer for other gaskets).
This work is far easier for a dealer or independent shop with experience on these engines (which have not been sold for 10 years).
Also, there are other things that can be best done with the plenum off, especially cleaning the throttle plate (seafoam good) and possibly replacing the fuel injectors (bosch rebuilt okay). But watch out for the seating gaskets for the injectors which sometimes need replacing (another dealer only part).
If you're crowding 150k miles, maybe new spark plugs wires (stay with Motorcraft).

If I didn't have several days of spare time, a good set of tools, and find joy in wrestling with the engine/plenum, and had a few hundred in the emergency fund, I'd have the dealer or a trusted independent shop do the work, and maybe have them clean the throttle plate while they're at it. Or live with the oil leak until you need to do the timing chain and all this stuff has to come of anyway. BTW, if you're smelling smoking oil, it's probably from the valve cover, not the main seal.
Main seal is a much bigger job, since it requires separating the trans from the engine.

 

[Sinonsenpai]

You've left out some important info, so hard to advise. How many miles? Body in good shape? Any prior engine work done? And especially, any chain rattle on cold startup? Do you love your SUV?

Valve cover gaskets are not a trivial job for DIY on the 4.0 SOHC. It can be done with lots of research and patience (may take a couple of days all told). The big challenge is removing the plenum (plastic intake manifold). The star bolts holding down the plenum are real hard to get to, and could strip. Best to remove hood and use step stool to get the rear few bolts. Use 1/4 inch ratchet and variety of extensions, swivel joint. I even used a couple different profile star bits. And think trips to Ford dealer parts department for replacements, and waiting several days for new bolts.
Rock Auto for valve cover gaskets and new plenum gaskets. I've had better luck with the German ones than Felpro (which I generally prefer for other gaskets).
This work is far easier for a dealer or independent shop with experience on these engines (which have not been sold for 10 years).
Also, there are other things that can be best done with the plenum off, especially cleaning the throttle plate (seafoam good) and possibly replacing the fuel injectors (bosch rebuilt okay). But watch out for the seating gaskets for the injectors which sometimes need replacing (another dealer only part).
If you're crowding 150k miles, maybe new spark plugs wires (stay with Motorcraft).

If I didn't have several days of spare time, a good set of tools, and find joy in wrestling with the engine/plenum, and had a few hundred in the emergency fund, I'd have the dealer or a trusted independent shop do the work, and maybe have them clean the throttle plate while they're at it. Or live with the oil leak until you need to do the timing chain and all this stuff has to come of anyway. BTW, if you're smelling smoking oil, it's probably from the valve cover, not the main seal.
Main seal is a much bigger job, since it requires separating the trans from the engine.

Thanks for the response I really appreciate it. I just bought it from a friends grandma less then a month ago. She kept all the receipts from all the work she had done to it and most of it was at the dealer . Looking through everything I dont see anything that was done to the engine. It just clicked over 106k miles on the dash. On cold start I dont hear any rattle or anything that would make me think it was starting to wear down the guides (yet). I know they are known for going bad as the miles go higher . Body is in what i would say ok/good shape. (Was garage kept since it was new up until 2014) No rust on frame. There was some on the door where you step to get in but previous owner had that cut out and new piece welded in. So far ya I am loving it . I am a bigger guy coming from a toyota corolla haha. besides the hard shifts sometimes into OD . Witch correct me if I am wrong mite be a solenoid pack needing replaced.

 

[Drewmcg]

Are you sure it's the OD? Easy way to verify its to turn off OD with the button and see if the hard shift goes away.
There's a neat repair for the OD piston wearing out the bore of the aluminum case. I did this to my '02 and it has shifted beautifully for several years, tends of thousands of miles. Best thing was did not require removing the trans. From Wisconsin.

Sounds like you got a gem (super low miles). With gasoline so cheap, this is a great vehicle for foreseeable future. It has its foibles (I've now replaced all four wheel bearings; two fronts @ 185k miles; two rears (much harder, took knuckles to a machine shop) @ 210k miles.
With good maintenance (regular oil changes, keep eye on coolant), the top end/cylinders are bulletproof. Just keep an eye on the plastic thermostat housing, which you WILL eventually have to replace. If it were me, I'd flush the system entirely and refill with Zerex G05 (gold) coolant. This is compatible with the Motorcraft coolant that Ford started using in late '02/'03, but not with the green stuff. It will be much longer life. Just be sure you run a hose of clean cold water through with engines running and heat on high for 15 minutes to flush thoroughly. Then drain radiator completely, and refill with 100% G05 ($20/gal @ Autozone), to achieve a 50/50 mix (b/c there will be lots of water left in engine).
Consider taking to a trustworthy trans shop to evaluate the trans. I would not assume solenoids.

 

[Sinonsenpai]

Are you sure it's the OD? Easy way to verify its to turn off OD with the button and see if the hard shift goes away.
There's a neat repair for the OD piston wearing out the bore of the aluminum case. I did this to my '02 and it has shifted beautifully for several years, tends of thousands of miles. Best thing was did not require removing the trans. From Wisconsin.

Sounds like you got a gem (super low miles). With gasoline so cheap, this is a great vehicle for foreseeable future. It has its foibles (I've now replaced all four wheel bearings; two fronts @ 185k miles; two rears (much harder, took knuckles to a machine shop) @ 210k miles.
With good maintenance (regular oil changes, keep eye on coolant), the top end/cylinders are bulletproof. Just keep an eye on the plastic thermostat housing, which you WILL eventually have to replace. If it were me, I'd flush the system entirely and refill with Zerex G05 (gold) coolant. This is compatible with the Motorcraft coolant that Ford started using in late '02/'03, but not with the green stuff. It will be much longer life. Just be sure you run a hose of clean cold water through with engines running and heat on high for 15 minutes to flush thoroughly. Then drain radiator completely, and refill with 100% G05 ($20/gal @ Autozone), to achieve a 50/50 mix (b/c there will be lots of water left in engine).
Consider taking to a trustworthy trans shop to evaluate the trans. I would not assume solenoids.

Thanks again for all the helpful info. I will give the the OD button trick a shot latter today when I take it out. I think I am going to at least take it to the shop and get the valve covers done . I really cant stand the oil burn smell . Haha. As much as I would like to do them myself and learn . I don’t have the space to leave a car half torn apart for a few days if I have to go to the ford dealer to order something. I got this explorer for $2000 witch I thought was a good deal. That’s why I want to try to fix it and keep up with it. The trans issue is what is got me the most worried. Was thinking about possiblely using this as a pop-up camper puller if it can handle it but still need to look up when tow rating is and what not.

 

[Drewmcg]

Thanks again for all the helpful info. I will give the the OD button trick a shot latter today when I take it out. I think I am going to at least take it to the shop and get the valve covers done . I really cant stand the oil burn smell . Haha. As much as I would like to do them myself and learn . I don’t have the space to leave a car half torn apart for a few days if I have to go to the ford dealer to order something. I got this explorer for $2000 witch I thought was a good deal. That’s why I want to try to fix it and keep up with it. The trans issue is what is got me the most worried. Was thinking about possiblely using this as a pop-up camper puller if it can handle it but still need to look up when tow rating is and what not.

It'll pull a pop-up camper no problem. Good luck; enjoy. PS, front tire pressure recommendation is 30 lbs (I think), which you should closely follow. (Double check.) Rear tires are higher. When they redesigned the front suspension in '06 MY they changed this.