7.3 thread continued?

[bdkw1]

Hemi=430fltb
Cummins=850-1050fltb

My stupid duty=650ftlb

Circling back to, TQ kills trannys, not HP. There is a reason it's not behind a diesel. They may be great trans, but until I see someone towing heavy with one in a diesel, I'm out.

 

[06h3]

I’m not saying this is the end all be all swap, just an FYI, like I said in my first post.

With that said, I have driven many 6-8-10 speed SUVs and trucks and the ZF 8HP is by far the best performing trans in my opinion, is it the best for a diesel? Maybe not but they do hold up to way more horsepower then they are rated for, not sure on torque.

They were also in the 3.0 eco diesel (480 TQ at 1600 rpm) which isn’t far off from a stock 7.3, pathetic….I know.


Would I put one in my 7.3? Hell no…at 20-30k gross, with 800 TQ, I am not a good test candidate.

With all that said, I’m intrigued to see where this goes for others, what I’d hope for is that the new Ram ZF powerline 8 speed trans behind the Cummins uses the same electronics as the 8HP. It is rated for 57k gross, and used up to “baby class 8” trucks.

It seems ZF builds one trans and uses it for many things. The 8Hp is used in so many applications and this powerline 8 speed is used in 2500 rams and can be used all the way through all class 5-6-7 and small class 8s.

If it is the same electronically you could use an SAE bellhousing adapter from the 7.3 to the powerline 8 and the same controller he uses. Long shot but ZF seems to keep thing simple, minimal parts for many applications

 

[bdkw1]

I’m not saying this is the end all be all swap, just an FYI, like I said in my first post.

With that said, I have driven many 6-8-10 speed SUVs and trucks and the ZF 8HP is by far the best performing trans in my opinion, is it the best for a diesel? Maybe not but they do hold up to way more horsepower then they are rated for, not sure on torque.

They were also in the 3.0 eco diesel (480 TQ at 1600 rpm) which isn’t far off from a stock 7.3, pathetic….I know.


Would I put one in my 7.3? Hell no…at 20-30k gross, with 800 TQ, I am not a good test candidate.

With all that said, I’m intrigued to see where this goes for others, what I’d hope for is that the new Ram ZF powerline 8 speed trans behind the Cummins uses the same electronics as the 8HP. It is rated for 57k gross, and used up to “baby class 8” trucks.

It seems ZF builds one trans and uses it for many things. The 8Hp is used in so many applications and this powerline 8 speed is used in 2500 rams and can be used all the way through all class 5-6-7 and small class 8s.

If it is the same electronically you could use an SAE bellhousing adapter from the 7.3 to the powerline 8 and the same controller he uses. Long shot but ZF seems to keep thing simple, minimal parts for many applications

Now you have my interest.

 

[06h3]

Interesting, kinda geeky guys but the ZF guy said they have quite a bit of similarities.

PowerLine

PowerLine, ZF’s 8-speed automatic transmission for Class 3 – Baby 8 trucks, designed with power, efficiency, and reliability for commercial vehicles

www.zf.com

 

[06h3]

This may suite your interest more

 

[AKnate]

It's surprising there's much interest in 30 yr old trucks and low horsepower engines.

I only have one because it was a decent truck at a good price, but I'm pretty well sick and tired of it being SUPER undependable.

I just want it to run right and nit CONSTANTLY need something else.
The last load of wood I tried hauling cost me a $225 tow. Randomly shut off and wouldn't restart. (No, not CPS, I walked home, got tools and a new CPS and changed it).
The amount if time I've spent in this truck is stupid at this point.

 

[Squamch]

It's surprising there's much interest in 30 yr old trucks and low horsepower engines.

I only have one because it was a decent truck at a good price, but I'm pretty well sick and tired of it being SUPER undependable.

I just want it to run right and nit CONSTANTLY need something else.
The last load of wood I tried hauling cost me a $225 tow. Randomly shut off and wouldn't restart. (No, not CPS, I walked home, got tools and a new CPS and changed it).

Other than the oil line letting go, and a few typical things like alternators and starters, mine has been quite dependable for the last 350,000 or so km.

 

[Provience]

This may suite your interest more

Thats the easy part, what are they using for the controller is the hard part

Well, the goal of being free from stock ecu is the hard part

 

[Provience]

It's surprising there's much interest in 30 yr old trucks and low horsepower engines.

I only have one because it was a decent truck at a good price, but I'm pretty well sick and tired of it being SUPER undependable.

I just want it to run right and nit CONSTANTLY need something else.
The last load of wood I tried hauling cost me a $225 tow. Randomly shut off and wouldn't restart. (No, not CPS, I walked home, got tools and a new CPS and changed it).
The amount if time I've spent in this truck is stupid at this point.

If new diesels weren't 70-100k and also had issues it'd make more sense to let the old diesels die

There's not much NA IDI love out there

 

[AKnate]

Other than the oil line letting go, and a few typical things like alternators and starters, mine has been quite dependable for the last 350,000 or so km.

In around 6 years... and not even 20k miles 3 starters, 3 or 4 sets of batteries, PSOM, turbo, 2 sets of injectors, injector cups, valve cover gaskets, glow plugs, up pipes, down pipe, trans pan, rear brakes 3x, rear wheel seals 4 times, front axleshaft seals, front hubs, steering shaft, headlight housings, trans cooler, thermostat and 3 upper hoses (aren't correct and end up rubbing the belt after a while) and I'm sure a few more things im forgetting.

In a truck with under 75k miles.

 

[Provience]

In around 6 years... and not even 20k miles 3 starters, 3 or 4 sets of batteries, PSOM, turbo, 2 sets of injectors, injector cups, valve cover gaskets, glow plugs, up pipes, down pipe, trans pan, rear brakes 3x, rear wheel seals 4 times, front axleshaft seals, front hubs, steering shaft, headlight housings, trans cooler, thermostat and 3 upper hoses (aren't correct and end up rubbing the belt after a while) and I'm sure a few more things im forgetting.

In a truck with under 75k miles.

You've also got the type of luck that wouldn't be able to keep a new truck out of the dealer warranty department:shrug:

 

[arse_sidewards]

It's surprising there's much interest in 30 yr old trucks and low horsepower engines.

With torque management modern trucks are making the same horsepower through the first three gears.

You've also got the type of luck that wouldn't be able to keep a new truck out of the dealer warranty department:shrug:

And he's in Alaska where everything gets rode hard and put away wet all the time.

 

[back woods]

In around 6 years... and not even 20k miles 3 starters, 3 or 4 sets of batteries, PSOM, turbo, 2 sets of injectors, injector cups, valve cover gaskets, glow plugs, up pipes, down pipe, trans pan, rear brakes 3x, rear wheel seals 4 times, front axleshaft seals, front hubs, steering shaft, headlight housings, trans cooler, thermostat and 3 upper hoses (aren't correct and end up rubbing the belt after a while) and I'm sure a few more things im forgetting.

In a truck with under 75k miles.

Flip side, I’ve been running my 7.3s for around 18 years. I’ve got 3 that have close to 300k that are all DDs, I consider myself a pretty staunch 7.3 owner but I have never; removed an injector (not even 1), removed an hpop, changed a thermostat, removed a fuel bowl or anything in the motor beyond a set of glow plugs. They just keep running and running. Run them hard and add oil when it’s not on the dipstick anymore.

 

[JR4X]

Flip side, I’ve been running my 7.3s for around 18 years. I’ve got 3 that have close to 300k that are all DDs, I consider myself a pretty staunch 7.3 owner but I have never; removed an injector (not even 1), removed an hpop, changed a thermostat, removed a fuel bowl or anything in the motor beyond a set of glow plugs. They just keep running and running. Run them hard and add oil when it’s not on the dipstick anymore.

How are them cold starts?

My uncle is a 7.3 nerd. Has one, a 01 that has over 400k miles on it. Only way it will start anymore is plugged in to the house and when it can’t get near an outlet needs ether.

 

[TrikeKid]

In around 6 years... and not even 20k miles 3 starters, 3 or 4 sets of batteries, PSOM, turbo, 2 sets of injectors, injector cups, valve cover gaskets, glow plugs, up pipes, down pipe, trans pan, rear brakes 3x, rear wheel seals 4 times, front axleshaft seals, front hubs, steering shaft, headlight housings, trans cooler, thermostat and 3 upper hoses (aren't correct and end up rubbing the belt after a while) and I'm sure a few more things im forgetting.

In a truck with under 75k miles.

Flip side, I’ve been running my 7.3s for around 18 years. I’ve got 3 that have close to 300k that are all DDs, I consider myself a pretty staunch 7.3 owner but I have never; removed an injector (not even 1), removed an hpop, changed a thermostat, removed a fuel bowl or anything in the motor beyond a set of glow plugs. They just keep running and running. Run them hard and add oil when it’s not on the dipstick anymore.

These two cases are the reality of mass produced ****. Sometimes you just get a bad one of a normally reliable machine. Sometimes people get a "good one" of a classically unreliable thing. My buddy's wife put 250k+ on a 3.0 4Runner and it never needed anything but scheduled maintenance, it got head gaskets under recall long before he bought it and after that it was stupid reliable.

 

[Squamch]

How are them cold starts?

My uncle is a 7.3 nerd. Has one, a 01 that has over 400k miles on it. Only way it will start anymore is plugged in to the house and when it can’t get near an outlet needs ether.

01 is at 580,000km and is smokey when it's cold, but it starts up not problem.

Now I think of it, I did do glow plugs, relay, and the UVCH as a preventative after one glow plug quit glowing. Pretty sure that was before my kids were born so 8+ years ago.

 

[Squamch]

In around 6 years... and not even 20k miles 3 starters, 3 or 4 sets of batteries, PSOM, turbo, 2 sets of injectors, injector cups, valve cover gaskets, glow plugs, up pipes, down pipe, trans pan, rear brakes 3x, rear wheel seals 4 times, front axleshaft seals, front hubs, steering shaft, headlight housings, trans cooler, thermostat and 3 upper hoses (aren't correct and end up rubbing the belt after a while) and I'm sure a few more things im forgetting.

In a truck with under 75k miles.

Well no ****. You're not driving it. Sitting kills trucks. Sounds like the last guy didn't drive it either with that mileage.

 

[TrikeKid]

Good glow plugs and relay has cured every hard starting 7.3 I've had to deal with. I used to get a ton of them through the shop with non-working or intermittent non-working relays that the owner just plugged in all the time because 7.3 owners are the kings of just ignoring **** while bragging on their reliability. Convincing them it wasn't normal to need to plug the thing in from September to March was harder than actually fixing the truck.

 

[back woods]

How are them cold starts?

My uncle is a 7.3 nerd. Has one, a 01 that has over 400k miles on it. Only way it will start anymore is plugged in to the house and when it can’t get near an outlet needs ether.

Smoke like trains but they always start, I swear by Powermaster 9051 starters.

 

[JR4X]

Well no ****. You're not driving it. Sitting kills trucks. Sounds like the last guy didn't drive it either with that mileage.

For his use for the truck, the same thing with a 460 instead of the diesel would have been a thousand times better. Some guys drink that common rail diesel koolaid though. It’s 9° outside today. I’m taking my 460 OBS to work on race cars instead of torturing the powerstroke to start.

 

[06h3]

Good glow plugs and relay has cured every hard starting 7.3 I've had to deal with. I used to get a ton of them through the shop with non-working or intermittent non-working relays that the owner just plugged in all the time because 7.3 owners are the kings of just ignoring **** while bragging on their reliability. Convincing them it wasn't normal to need to plug the thing in from September to March was harder than actually fixing the truck.

This….so many kids brag their 7.3 won’t start under 40° like it’s cool.

That truck house YouTube guy has his OBS 7.3 in Alaska and it fires off pretty quick in -30, because he maintains his **** with good batteries, and a working glow plug system.

The only time I saw it didn’t start for him was when the diesel gelled up.

 

[speed bump]

This….so many kids brag their 7.3 won’t start under 40° like it’s cool.

That truck house YouTube guy has his OBS 7.3 in Alaska and it fires off pretty quick in -30, because he maintains his **** with good batteries, and a working glow plug system.

The only time I saw it didn’t start for him was when the diesel gelled up.

Yeah that dude is full of **** when he talks about temperatures. It was like 0 with a -20 wind-chill. When it actually was -30 f it didn't start. From experience on a well maintained 7.3 with good batteries, at least 6 good glow plugs, a working fuel bowl heater, and 5w-40 synthetic they will usually start down to -20°f not plugged in. At -40 it's a gamble whether or not it will start plugged in. In contrast my 6.7 it's a gamble whether or not it starts at -40 not plugged in but it has always started at -30 f.

 

[6869704x4]

Hopefully I'll never find out if mine will start at -40

 

[reptillikus]

Yeah really
I know mine starts without the block heater at 0°, and that's good enough for PA

 

[AKnate]

Well no ****. You're not driving it. Sitting kills trucks. Sounds like the last guy didn't drive it either with that mileage.

Just used for hauling. Same as my 5500. That one just broke 100k miles. Bought it in 2020 with around 85k

 

[bdkw1]

I've started mine at -3 without plugging in. Not doing that again, sounded like it was going to chuck a rod. Now if it's below freezing it gets the heater. Would it start without it, yes, but it scares the **** out of me.

 

[KungFooMASTA]

I've started mine at -3 without plugging in. Not doing that again, sounded like it was going to chuck a rod. Now if it's below freezing it gets the heater. Would it start without it, yes, but it scares the **** out of me.

Thats how I feel. No reason to be harder on things than you have to be. If you can plug it in why not.

 

[Squamch]

Thats how I feel. No reason to be harder on things than you have to be. If you can plug it in why not.

I plug mine in. My next door neighbour doesn't. He starts his at 615am, I start mine at 640am.

Plus then my heat works when I get in, not 15 minutes down the road.

 

[6869704x4]

Old video when it only had 200k on it. 17 degrees and four working glow plugs. Stock as far as I know
Fail, can't upload
Says the video is too big.

 

[AKnate]

For his use for the truck, the same thing with a 460 instead of the diesel would have been a thousand times better. Some guys drink that common rail diesel koolaid though. It’s 9° outside today. I’m taking my 460 OBS to work on race cars instead of torturing the powerstroke to start.

I've not had any issues with it starting from cold, especially not at warm temps like 9*.
Almost all my stuff is diesel, I don't normally plug anything in unless it's well below zero.

Not many gas engine C&C OBS around here. This one was from BP. Until ULSD came about most of their fleet was diesel as they refined their own fuel from oil just a bit down the pipe.
They had hundreds of 7.3s and 6.0s.
I've seen some trucks with over 30,000 hrs... so like 1,000,000 miles.
Even now, there's lots of equipment and trucks that stay running 24x7, only shut down for an oil change every 21 days.

Now most of the light duty is gas converted to propane which they make for near free.