For all the trans guys out there- I have no idea & this is probaly a dumb question, but why doesnt someone build an upgraded 5 or 6 gear trans for out 7.3 trucks or is that even possible ?

 

Sure it's possible. I've got a 6 speed behind my 7.3

For the 2 pedal crowd, it comes down to, yes it can be done, but the cost of development and production means not enough will sell to make it a worthwhile venture.

Besides, you're likely talking about adding intermediate gears, not changing the final overdrive ratio (much) so I'm not really sure how much of an actual improvement you would see from doing this.

 

A lower-ratio first gear (in the 3.5-3.75:1 range would be nice), lower the second gear ratio slightly (1.7:1-ish), and make the new 5th gear somewhere in the .85:1 range.

The gear ratios would then be 3.75, 2.48, 1.7, 1, .85, .75:1 Oh, and lower the absurdly-high reverse to about 3.25:1 whilst in there. Yes, I know what it would take planetary-wise to make the ratios and what is/is not possible there concerning ratios but these are just pipe dreams anyway.

 

The automatic trucks suffer the same fate as the 6-speeds. If the gear split between 5th and 6th was the same as 4th and 5th it would be MUCH nicer. The 3-4 shift in the automatics is just as dismal.

 

It's only dismal when towing heavy. And actually, I take more exception to the 3-4 shift (or 2-3 if you count it as a 5 speed plus granny). Too big a jump there for my liking, but seeing as how I have 6 gears forward, it's kind of hard to complain too much.

As for reverse, I hear you. I never understood why Ford seems to love the 30 mph reverse gear the auto's seem to have. The ZF reverse is 5.23:1 and I think that seems to work just fine.

 

Four of the 7.3L pickups at work have 6 speeds but I don't drive them much. My F-550 has one, but it has 4:88 gears and I never really use 2-3 gear that much so I don't pay much attention. However, it weighs 17,500+ lbs. and the hills around here make the whole 6-5 downshift thing really annoying but the 4-5 is terrific.

If anyone here has ever driven a Duramax (I made a good living repairing those for close to a decade), the Allison, while severely over-rated, has the perfect gear splits when paired with the diesel. Full-onion shifts resulted in a nearly clockwork 3300 to 2700 RPM upshift for every gear. Add in the fact that you'd need to be in neutral, downhill, and with a headwind to back up faster than 15 MPH and you've got the perfect gear ratios.

I've done 36 MPH in reverse. That's just retarded. Shifting to low range just to back up without burning up the transmission makes no sense to me either.

 

A buddy of mine has a duramax/allison & every time he lets me drive it I think how nice it would be to have that trans in my truck.

 

I would be very nice if some one would do it. I like how the 5R110 works much better also. But there final gear is the same as ours.

 

It can be done, just really expensive.

Buy a 5r110, adapter plate, and PCS stand alone controller along with wiring harness. Install.

Connect PCS to the trans. Run the appropriate trans tuning. Make adjustments as necessary. Done.

PCS alone will cost you nearly a grand. And a good 5r110 isn't cheap either. Then there's that damn adapter plate. Think the cheapest I saw one a few years ago was around $750, if they are still around anymore.

So on top of an already more expensive 5-speed over the 4-speed, you're going to spend even more money on top of it to make the conversion. Hence why most people don't do it, just doesn't seem worth the money for 1 extra gear tossed in there. Especially when you can spend the money on a fully built 4r100 and have a completely bullet proof trans. $6K-$7K for the conversion, or $3K-$4K for a bullet proof 4r100?

 

yup, 4-5 (if counting L as 1) is absolute a wetdream, BUT, 3-4 (if counting L as 1) like what Chris mentioned, is downright a DOG.

"Doing 35mph in reverse is just retarded"....HAHA

 

Thanks for that Curtis - Thats what I was wondering - It would be worth an extra grand or so but double the price of a bts or jw is a tough pill to swallow.

 

ever looked into... gear vendor?

 

Of course it's possible. ANYTHING is possible. If you will give me enough time and money I can install ANY transmission you want. I can even design one with any number of gears that you want.

Is it practical? Not even close. HERE is why.

 

Tim- No I havent but will
Mark - Thanks for the insight - I had a notion it would be pretty expensive - Guess I'll keep mine the way it is till it gives me a reason to upgrade to a HD trans.

 

https://www.gearvendors.com/f2wd4s.html