I have a 02 7.3 crew cab lifted with 37 s on it,I tow a 25 ft toy hauler with a gvwr of 10,500,my truck is stock exept for exhaust and lift.the gears are 3:73 ratio and was wondering what I should do to improve my towing.I am not overly concerned about the milage as i am about the destruction of my transmission and driveline,I have been told to get a tuner before I do my gears but i feel it should be the opposite,I am looking for some direction as i am new to diesels and towing.what I have been doing in the mean time is just been driving real mellow with easy acceleration and no abrupt throttle ever,but i did let my brother drive the rig and he sapped a u joint,but I told him not to worry you wont snap another u joint after I fix it, and he said why ,and i said because you are never going to drive it again,simple fix.I just need some advice from people who have the experience,thaks Steve

 

If you plan to keep the large tires, your only good option is changing gear sets in the differentials.

That's a lot of weight to be moving with big meats.

Do you have a point-n-shoot IR thermometer? If so, what's the rear differential cover measure after a hundred miles or so?

Pop

 

I agree with you doing gears before tuner with 37s. What gear ratio are you thinking about going with? Don't know if you have 4wd or not, if you do it can get kind of expensive though.

 

It is a 4x4,and thats what I wanted help on also what gears to run

 

and no I do not have a point and shoot

 

I would run 4.10s. If you tow the majority of the time you might want to look at 4.30s.

 

what would my top speed be with 4.10 and 4.30s and also where is a good affordable place to get my gauges and what gauges are a must or most important

 

If you lower your gearing the same percentage as you have increased your tire circumference, your speed and other performance parameters should be about the same as they were before the tires.

It's all just math.

You WILL, however, need to re-calibrate your speedometer to ensure proper shift points.

Pop

 

I went the other route. For 37's I was happy with the RPM range, I could still get 15-17 mpg. if I towed, I just kept it out of OD and kept the RPM's up. If I didn't like the way it shifted, then I shifted it manually...

Get yourself a chip, intake, guages, a large tranny cooler (31 Row 6.0 one), a valve body, then a wicked wheel. You can do all of that for less then the price of the gear swap. Then see if you like it...

If you do gear it, 4.30's at the most. You will be sitting at 1940 rpms at 70 mph (OD)... and 2300 at 60 mph (NO OD)...

4.10's will give you around 1850 at 70 mph in OD and 2200 at 60 (NO OD).

Or stick to where you are at... 1700 RPM's at 70 in OD and 2000 RPMs at 60 (NO OD)

Find someone nearby with AE or pick it up from Clay at Riffraff Diesel and recalibrate your speedo...

 

what is AE,where is a good place to get gauges,and what is awicked wheel

 

AE is automotive Enginuity... Riffraff Diesel: Total Ford Enhanced Bundle

You can monitor all sensors in the motor, pull codes, change your speedo for up to 40" tires...


You will most likely see a little turbo surge with the addition of a chip, cheapest way to cure that is the WW...

Riffraff Diesel and you can find your gauges and wicked wheel.

 

I have all this done minus the VB, the tuner has done a great job of firming up the shifts, thoughs long grinding smoooooth shifts used to make me cringe...................................

I was going to do gears now I am on the fence as to the gears, I can run steeper grades without shifting and utilize OD.

The trans cooler is also a advise keep it cool. My rear LS is B/0 (bad order) so I am not worried about that. I try to go easy off the line and watch my shifts. The intake will feed you air hungry engine and help EGT's, anything you can do to keep your EGT's lower will help run a higher HP tow tune.

I am pulling a 30' Cougar around #8000

 

Layson, I don't know where you get those rpm numbers, but I have 4:10 in my dually and run 1900 rpm's at 62 mph in over drive.

 

I think Layson was talkin' about 37 inch tires. Are your tires on your DRW 37's may be the difference................

 

what size tires are you running?