'96 OBS F250 7.3 questions...

[LBsuperJET]

Hey all,

Will be purchasing a 96 7.3 F250 4WD ext cab long bed later this week. It has just over 300k miles and is VERY clean in my opinion. Test drove it and it tracked very straight and drove very nicely. Most miles were long highway miles and it was very nicely taken care of. Has a newer transmission (I know, E4OD sucks), and supposedly no major motor work done yet. New starter and batteries.

Being that this is my first diesel that I will own, I dont know very much about its popular quirks.

The plan is to use it for my mobile welding work for the next couple of years. I even have a Douglass welding body ready to go on it.

My question is for you seasoned 7.3 owners, what are the things I need to keep an eye out for, and what are the best upgrades for safe power and longevity?

Thanks in advance to some of RDP's best!

 

[mash on it]

Nice

Dan'l

 

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Confirm the mileage is correct. On the OBS Fords the odometer goes all the way to 399,999.9 then resets back to 300,000.0 instead of going to 400,000.0. So it could have 400K, 500K, ect. The twin traction beam 4wd sucks. I swapped a 89 F350 Dana 60 into my 95 F250 when I had it. 89 model year has kingpins. Look into it. If you swap a Dana 60 in make sure the bolts that hold the tracbar bracket in place are positioned that the head of the bolt is facing the oil pan. If you have the nut facing the pan the bolt is to long and will rub a hole into the oil pan. The twin traction beam brackets on the cross member like to crack and break.
The brakes suck and in an emergency slam the brakes on, there is a bypass in the master cylinder that will open so you have no brakes in a oh shit panic brake situation. The stamp steel cover on the transmission for the torque converter likes to crack the tabs for the bolts and then it rubs a hole in the back of the oil pan. If you hear a popping noise when turning in reverse the passenger fender bolts are loose and need to be tightened.
The mechanical fuel pump gets tired and needs replacing. It's in the valley of the engine. Be careful when removing it so the plunger doesn't fall into the engine. The orange silicone boot on the intake side of the turbo tears and allows dirt into the engine. Get a new upgraded one from Riffraff Performance. The stock airbox is a piece of shit that has plastic bolts that break so the airbox doesn't seal and allows dirt into the engine. Best upgrade is the 6637 air filter mod then an upgraded downpipe. The factory one is a restrictive flattened POS. The injector O rings on the OBS 7.3's weren't that good at the time and will allow oil to leak into the fuel galley and cause smoke on startup. Pull the fuel filter cap and if the fuel is black then the O rings are bad.

 

[LBsuperJET]

Confirm the mileage is correct. On the OBS Fords the odometer goes all the way to 399,999.9 then resets back to 300,000.0 instead of going to 400,000.0. So it could have 400K, 500K, ect. The twin traction beam 4wd sucks. I swapped a 89 F350 Dana 60 into my 95 F250 when I had it. 89 model year has kingpins. Look into it. If you swap a Dana 60 in make sure the bolts that hold the tracbar bracket in place are positioned that the head of the bolt is facing the oil pan. If you have the nut facing the pan the bolt is to long and will rub a hole into the oil pan. The twin traction beam brackets on the cross member like to crack and break.
The brakes suck and in an emergency slam the brakes on, there is a bypass in the master cylinder that will open so you have no brakes in a oh shit panic brake situation. The stamp steel cover on the transmission for the torque converter likes to crack the tabs for the bolts and then it rubs a hole in the back of the oil pan. If you hear a popping noise when turning in reverse the passenger fender bolts are loose and need to be tightened.
The mechanical fuel pump gets tired and needs replacing. It's in the valley of the engine. Be careful when removing it so the plunger doesn't fall into the engine. The orange silicone boot on the intake side of the turbo tears and allows dirt into the engine. Get a new upgraded one from Riffraff Performance. The stock airbox is a piece of shit that has plastic bolts that break so the airbox doesn't seal and allows dirt into the engine. Best upgrade is the 6637 air filter mod then an upgraded downpipe. The factory one is a restrictive flattened POS. The injector O rings on the OBS 7.3's weren't that good at the time and will allow oil to leak into the fuel galley and cause smoke on startup. Pull the fuel filter cap and if the fuel is black then the O rings are bad.

Awesome stuff, thank you!

 

[Gelcoater]

Hey all,

Will be purchasing a 96 7.3 F250 4WD ext cab long bed later this week. It has just over 300k miles and is VERY clean in my opinion. Test drove it and it tracked very straight and drove very nicely. Most miles were long highway miles and it was very nicely taken care of. Has a newer transmission (I know, E4OD sucks), and supposedly no major motor work done yet. New starter and batteries.

Being that this is my first diesel that I will own, I dont know very much about its popular quirks.

The plan is to use it for my mobile welding work for the next couple of years. I even have a Douglass welding body ready to go on it.

My question is for you seasoned 7.3 owners, what are the things I need to keep an eye out for, and what are the best upgrades for safe power and longevity?

Thanks in advance to some of RDP's best! View attachment 1128558
View attachment 1128559

Be prepared to get behind the dash.
Things may have changed between 91 and 96 but my 91 had some AC control issues.
A lot of it is vacuum actuated.
Is sort of a pain in the ass to pull it apart but not horrible.

 

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Be prepared to get behind the dash.
Things may have changed between 91 and 96 but my 91 had some AC control issues.
A lot of it is vacuum actuated.
Is sort of a pain in the ass to pull it apart but not horrible.

91 was the last year of the brick nose. It has slide type climate controls. 92-97 is the timeless look and has knob type climate controls. The only vacuum problem I had on an 88 was a vacuum leak that kept the A/C from being able to go to A/C max. I just put tape on the leaking line. My 95 worked well and was ice cold.

 

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Another thing too, I'm trying to remember correctly here, is if the 3rd brake light or taillights aren't working check the dome light bulb. Or there's something related to all 3 of those for them to work. If you do swap to a solid axle look into the PMF reverse shackle kit and use V and B code leaf springs from a Superduty, 99-04 truck. V codes are front, B codes are rear. Be easy on the fuel tank selector. Push to hard it falls into the dash.

 

[LBsuperJET]

Brought it home today. The thing tracks nice and straight and rides very well. I already found a small fuel leak off the fuel bowl and running off the back of the engine lol. Gonna grab the o-ring kit and get that taken care of.

 

[mash on it]

There's a plug in the back of the hpop that's known to leak. It goes down the valley and down the bell housing area and mimics a rear main oil seal leak, fyi

Dan'l

 

[mash on it]

Just in case.

Dan'l

 

[LBsuperJET]

There's a plug in the back of the hpop that's known to leak. It goes down the valley and down the bell housing area and mimics a rear main oil seal leak, fyi

Dan'l

That's EXACTLY what I thought at first. Gotta be it.

 

[LBsuperJET]

View attachment 1129914
Just in case.

Dan'l

Perfect, thank you very much. Gonna look for these now.

 

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That's EXACTLY what I thought at first. Gotta be it.

The plug doesn't leak, it pours. I bet it's the charge air boots, o rings on the turbo pedestal, or the EBPV actuator is leaking where the rod comes out. Sometimes the plugs on the back of the heads will leak.

 

[LBsuperJET]

The plug doesn't leak, it pours. I bet it's the charge air boots, o rings on the turbo pedestal, or the EBPV actuator is leaking where the rod comes out. Sometimes the plugs on the back of the heads will leak.

I was hoping it would be off of the fuel bowl, but I will check all those too. Sounds like these motors love to leak. Everywhere.

 

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Only use Ford gaskets and o rings. If you use a parts store gasket on the HPOP resivior cap it will break the front cover. Engine has to be pulled out to fix that.

 

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I was hoping it would be off of the fuel bowl, but I will check all those too. Sounds like these motors love to leak. Everywhere.

They have some common stuff. If you keep up on the oil changes they're less likely to leak. Going 10K mile oil changes is bad.

 

[LBsuperJET]

They have some common stuff. If you keep up on the oil changes they're less likely to leak. Going 10K mile oil changes is bad.

Ok, gotcha. Oil is the first thing I am going to do anyway. After that, I am probably going to swap all of the affordable sensors as a precaution, in addition to figuring out the fuel leak.

 

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Check the fuel pump and fuel lines. Does the fuel pump have a black plastic thing behind it that says Bosch on it?

 

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The banjo bolt on the back of the fuel pump comes loose and will cause a fuel leak.

 

[LBsuperJET]

Check the fuel pump and fuel lines. Does the fuel pump have a black plastic thing behind it that says Bosch on it?

The banjo bolt on the back of the fuel pump comes loose and will cause a fuel leak.

Ahh, good to know. Dark now but I will check tomorrow while my tri tips are smoking away

 

[BamBam]

You have front leaf springs. That means you already have the Solid axle not the TTB. No upgrade needed.

I just sold a '96 2wd CCLB 7.3L. I liked that truck. We fought a few oil and diesel leaks from the valley area. As stated above there are several potential sources and they are all a little challenging to diagnose with how tight everything is in the valley. All of the leaks in the valley run out the hole at the back of the block. We ended up replacing the fuel pump, both high pressure soft lines as well as all of the little blue fuel lines and we rebuilt the fuel bowl o-rings. We replaced the o-ring on the back of the HPOP. We had a strange issue with the injector harness and replaced the valve cover gaskets and glow plugs then repaired the wiring on the engine harness side. We removed the EBPV (Exhaust Back Pressure Valve) to eliminate the potential oil leak as that valve is actuated with engine oil pressure. All in all they are really good trucks. You know the trans can be a weak point. I told my son we would not do any power mods with 300,000+ on the odometer cause the stock tune kept it together for the first 300,000+ There are plenty of hop-ups for the 7.3 and they are smog exempt so you can really do anything with them. I was going to wait until it wore out and when we replaced the engine we would hop it up then.

Like stated above use Ford parts if you can find them.

 

[Your ad here]

You have front leaf springs. That means you already have the Solid axle not the TTB. No upgrade needed.

I just sold a '96 2wd CCLB 7.3L. I liked that truck. We fought a few oil and diesel leaks from the valley area. As stated above there are several potential sources and they are all a little challenging to diagnose with how tight everything is in the valley. All of the leaks in the valley run out the hole at the back of the block. We ended up replacing the fuel pump, both high pressure soft lines as well as all of the little blue fuel lines and we rebuilt the fuel bowl o-rings. We replaced the o-ring on the back of the HPOP. We had a strange issue with the injector harness and replaced the valve cover gaskets and glow plugs then repaired the wiring on the engine harness side. We removed the EBPV (Exhaust Back Pressure Valve) to eliminate the potential oil leak as that valve is actuated with engine oil pressure. All in all they are really good trucks. You know the trans can be a weak point. I told my son we would not do any power mods with 300,000+ on the odometer cause the stock tune kept it together for the first 300,000+ There are plenty of hop-ups for the 7.3 and they are smog exempt so you can really do anything with them. I was going to wait until it wore out and when we replaced the engine we would hop it up then.

Like stated above use Ford parts if you can find them.

4WD F250 trucks have TTB, not a solid axle. Yes, I beam 4WD with leaf springs. TTB is different than I beams. 2WD is I beams. I know because first thing I did was rip that Dana 50 TTB out of my 95 F250 and swapped in a 89 F350 Dana 60. A plug in tuner won't cause these engines to break internal parts. The question is at 300K miles is this engine tired because of the air filter housing breaking or is it healthy. Either way a tune won't hurt it. Just you'll feel less gain on a tired engine.

 

[mash on it]

Over 600k on mine, and 389k when I did a few mods for more efficient HP/TQ. Not unusual to find million miles motors still running around.
The newest 7.3PSDs are almost 20 years old. Over 2 million were built between 94.5 and 2004. As of 2015, only 1.5 million Cummins (5.9s AND 6.7s); were built, since 1988. So there's that.
Yeah it's a slow dog, but don't mind the mule, just load the wagon.

Dan'l

 

[BamBam]

4WD F250 trucks have TTB, not a solid axle. Yes, I beam 4WD with leaf springs. TTB is different than I beams. 2WD is I beams. I know because first thing I did was rip that Dana 50 TTB out of my 95 F250 and swapped in a 89 F350 Dana 60. A plug in tuner won't cause these engines to break internal parts. The question is at 300K miles is this engine tired because of the air filter housing breaking or is it healthy. Either way a tune won't hurt it. Just you'll feel less gain on a tired engine.

I stand corrected. Thanks for the info. I thought some were TTB and some were straight axle, but that wasn't correct

 

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I stand corrected. Thanks for the info. I thought some were TTB and some were straight axle, but that wasn't correct

That era of truck, 80's to 90s the 4wd F250's are TTB. The 4wd F350's are straight axle. Some of the early 80's 4wd F350's had factory TTB.

 

[ibelio]

don't register to a business in cal dmv won't do it because of smog [personal ok]

 

[LBsuperJET]

don't register to a business in cal dmv won't do it because of smog [personal ok]

I did not. Absolutely no way I would even try. Just transferred ownership and insured it yesterday so good to go! For now lol

 

[LBsuperJET]

Hey all, some updates...

Still chasing that fuel leak on top of the motor. After learning about the whole fuel bowl and pump bullshit I'm confident I will find it soon LOL. Slapped that welding body on it last week and just got all of the LED lights figured out out back. Had to put load resistors on the tail/brake lights and everything is just a simple swap. Here is a pic of the day we swapped beds. And no, don't worry I'm not getting rid of the stock bed! Not getting rid of the TTB front end but at some point will go with Solo Motorsports' leaf spring delete kit. Superduty lift coils and big ass radius arms. This thing rides like shit in the front.

 

[RogerThat99]

I had a 97 F350 PSD for about 5 years. I didn't have any of the problems with fuel leaks and oil leaks, but I bought it 3 years old with 60,000 on it. Sold it with 150,000 on it. It was a great truck. Lifted, it rode like a covered wagon though. LOL.

The truck was kind of a dog, especially when towing. I put an Edge Evolution tuner on it, and just ran it on the Tow/Haul tune. The engine didn't have the fuel delivery system to run the high HP tune. I also had an air box, larger down pipe off the turbo, and 4" exhaust. I

I towed 12,000 lbs a lot with it, and hauled 4,000 - 5,000 in the bed frequently. It did great once I tuned it. I also put a 16" x 16" transmission cooler in it. The stock cooler was so small, I wouldn't run it in a Pinto.

 

[LBsuperJET]

I had a 97 F350 PSD for about 5 years. I didn't have any of the problems with fuel leaks and oil leaks, but I bought it 3 years old with 60,000 on it. Sold it with 150,000 on it. It was a great truck. Lifted, it rode like a covered wagon though. LOL.

The truck was kind of a dog, especially when towing. I put an Edge Evolution tuner on it, and just ran it on the Tow/Haul tune. The engine didn't have the fuel delivery system to run the high HP tune. I also had an air box, larger down pipe off the turbo, and 4" exhaust. I

I towed 12,000 lbs a lot with it, and hauled 4,000 - 5,000 in the bed frequently. It did great once I tuned it. I also put a 16" x 16" transmission cooler in it. The stock cooler was so small, I wouldn't run it in a Pinto.

View attachment 1142845

Great looking truck man. Mine also has the Edge Evolution 6 position chip tuner on it. The tow/tune level 3 is perfect for daily driving mine too. It also already has a 4" turbo back exhaust which is nice that I wont have to pay for it all. This wont tow prob at all as long as its being used as a weld rig so that's good.

 

[Bobby_329]

Hey all, some updates...

Still chasing that fuel leak on top of the motor. After learning about the whole fuel bowl and pump bullshit I'm confident I will find it soon LOL. Slapped that welding body on it last week and just got all of the LED lights figured out out back. Had to put load resistors on the tail/brake lights and everything is just a simple swap. Here is a pic of the day we swapped beds. And no, don't worry I'm not getting rid of the stock bed! Not getting rid of the TTB front end but at some point will go with Solo Motorsports' leaf spring delete kit. Superduty lift coils and big ass radius arms. This thing rides like shit in the front. View attachment 1142835
View attachment 1142836
View attachment 1142837

I would look into the fuel bowl delete, those things always leak and you don't really notice it till its bad because it all ends up in the valley. Looks super clean for an obs

 

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I would look into the fuel bowl delete, those things always leak and you don't really notice it till its bad because it all ends up in the valley. Looks super clean for an obs

I think if you do a fuel bowl delete on an OBS you have to convert it over to electric fuel.

 

[the510]

Sometimes the valve that opens and closes to drain the fuel bowl collects Dirt and grime. Then in will not completely close. This will trip into the valley, and out the drain right in front of the transmission.

If you don’t know already RIFF RAFF Diesel is by far the best truck site for the 7.3s.

 

[intense]

I would look into the fuel bowl delete, those things always leak and you don't really notice it till its bad because it all ends up in the valley. Looks super clean for an obs

What is the fuel bowl delete?

 

[Bobby_329]

What is the fuel bowl delete?

It gets rid of the fuel filter bowl in the valley that always ends up leaking and gives better fuel flow.

 

[Your ad here]

Hey all, some updates...

Still chasing that fuel leak on top of the motor. After learning about the whole fuel bowl and pump bullshit I'm confident I will find it soon LOL. Slapped that welding body on it last week and just got all of the LED lights figured out out back. Had to put load resistors on the tail/brake lights and everything is just a simple swap. Here is a pic of the day we swapped beds. And no, don't worry I'm not getting rid of the stock bed! Not getting rid of the TTB front end but at some point will go with Solo Motorsports' leaf spring delete kit. Superduty lift coils and big ass radius arms. This thing rides like shit in the front. View attachment 1142835
View attachment 1142836
View attachment 1142837

So since you have taken the pickup bed off and replaced it with now a non pickup bed the registration classification changes, maybe. I dont know if the less than 10,000 GVWR exemption is still active in Ca. Whatever you do, fly under the radar and if anyone ask, it has a pickup bed on it, no matter what.
If you have to register it as commercial vehicle for hire, which the bed makes it, you'll need CA numbers, motor carrier permit, weight declaration (expensive), and a $750K minimum insurance policy. That's if the less than 10,000 GVWR exemption went away.
It's all dumb but it's what the state of Ca does.