Gears or more horses?

[rubberduck]

The truck weighs 11k currently. It has 4.10's on 34's. The tranny still searches at around 60-65 which is mostly what we do on the big road. I'm trying to decide between deeper gears(4.88) or more power(programmer) to push it down the road. Any advice from those with heavier rigs would be appreciated.
7.3 with a fresh 4r100

 

[IdaSHO]

A good chip/tune would do it.

I run a TS performance 6-position chip.
Have been for many years.

When i got mine they were the go-to for "canned" tunes.

Not sure if thats still the case.

 

[IdaSHO]

FYI, Im rolling at 10k lbs, and running 3:55 gears.

With the chip and 33" tires its perfect.

Plenty of power, and great MPG

 

[F350joe]

I run a Hydra tuner and have like 12 tunes loaded up on it with everything from heavy tow to fuel sipping. You can even get a custom tune to manage your shift points a little better, only cost like 50 bucks last I checked. I also have a gear vendor gear splitter. Just tap the button on the floor and it either down shifts a half gear or upshift half a gear depending on engine load.

Finally, check you overdrive wiring on the column, common wear point. You could just be going in an out of overdrive.

 

[rubberduck]

FYI, Im rolling at 10k lbs, and running 3:55 gears.

With the chip and 33" tires its perfect.

Plenty of power, and great MPG

How much is great? Did you install an intercooler?

 

[rubberduck]

I run a Hydra tuner and have like 12 tunes loaded up on it with everything from heavy tow to fuel sipping. You can even get a custom tune to manage your shift points a little better, only cost like 50 bucks last I checked. I also have a gear vendor gear splitter. Just tap the button on the floor and it either down shifts a half gear or upshift half a gear depending on engine load.

Finally, check you overdrive wiring on the column, common wear point. You could just be going in an out of overdrive.

Gear splitter is on the wishlist. I'm pretty sure it's the lack of power causing the search. I can set the cruise at 75 and it's more in the power band and works great.

 

[Deleted member 9101]

Definitely up the HP.

 

[IdaSHO]

How much is great? Did you install an intercooler?

As pictured, we have averaged a solid 14MPG over the course of 50k+ miles

No intercooler. Have never seen the need.

She can get cookin' on long grades, but its a simple matter of slowing down and dropping a gear to keep the EGTs in the green.

The 7.3s need RPM to keep EGTs down. Don't ever lug them up hills, that's a great way to cook them

 

[rubberduck]

As pictured, we have averaged a solid 14MPG over the course of 50k+ miles

No intercooler. Have never seen the need.

She can get cookin' on long grades, but its a simple matter of slowing down and dropping a gear to keep the EGTs in the green.

The 7.3s need RPM to keep EGTs down. Don't ever lug them up hills, that's a great way to cook them

How big of a tune are you running? I was thinking around 60-80 would wake the old girl up.

 

[IdaSHO]

Honestly dont remember just how hot the tunes are rated, but Ive always run it in the lowest setting which was only 30hp I believe.
Ive found that the lower tune for whatever reason works better with the old E40D trans than the hotter tunes.
It also returns better MPG, and keeps the EGTs in the green longer.

Also, my early 7.3 has considerably lower flow injectors than yours, and simply wont see the big gains that yours can.

 

[rubberduck]

The hydra is on its way. It'll be nice to have a little power. Thanks for the insight.

 

[Oldcarnut]

With my 10k pound 7.3, I noticed a 4 inch exhaust helped with my 35s and 4.56 gearing. Need a tuner and kind of wish I had stayed 4.10s for fuel mileage (average 8.5 mixed driving).

 

[IdaSHO]

You are 100% correct in thinking that taller gear would get you more MPG.

These motors have plenty of torque pretty much right off idle, gobs more with a chip/tune
In order to maintain good MPG in my experience, cruising RPM should be between 1600 and 2000 RPM
Above 2k, and you will be drinking fuel. Below 1500RPM or so, and you are lugging (assumed loaded), and is bad for many reasons, especially with an auto trans.

My truck running 3:55s and 33's...

Empty with cruise set at 65-70 MPH is a true 20MPG truck
Loaded to 10k, obviously it varies. Outside temp, tire pressure, wind, and especially winter/summer fuel blends play a big role in MPG.
But average across the board is a hair above 14MPG

 

[rubberduck]

The hydra certainly fixed the searching issue. With the 80 horse tow tune it doesn't miss a beat now. It really woke this thing up.

 

[digitalnomad]

Typically, tunes on a gas engine would lean out the air/fuel ratio to gain more power. Factory tunes are a safe bet. For those reasons and only two options to solve your problem, I'd add more gear. Unless you hire a tuner and get a custom tune where he dyno tests it and then road tests it in the environment and load conditions that you will be traveling in. The end result will probably be a factory tune in that case, unless you install a custom cam, headers and get more air in prior to the tuning.