7.3 and Hills - Page 7

BajaSportsmobile · 12-01-2015, 07:14 PM

So, what have you decided for gear ratio?

Quote:

Originally Posted by 1der

^^ Thanks Rick for all the follow up and attention to this. Very tmely for me.

Just back from three weeks and a couple thousand miles through AZ and So Cal. I was vacillating about what to do with ratios, tunes, etc. Have a 2002 7.3 (stock) w 3.55 gearing and 285/70-17's. Running the AR9100 additive in the oil (now second application) and using their fuel additive as well. Was pretty loaded up with gear (far more than needed, but

). Climbing the hills, engine would drop out of OD and spend some time around 2400 rpm but still kept mid 60 mph speed which was fine.

Stopped by Strictly Diesel in Phoenix and had them install a Tru-Cool trans cooler, also had them do the scheduled 55k mile oil change. Nate and the Gary are awesome guys and I am super happy with the results. Trans cooling is much better. They said engine sounded great in the test drive before the work..

Also spoke to them about tuners, ratios, etc. If not towing, they said stick with the 3.55's, and said a DP chip was fine and best for the vans, in their opinion. Will also add EGT gauge to keep an eye on those.

Looking forward to the DP Chip in the very near future!

E350 · 12-01-2015, 07:20 PM

See Ken Gregory's post here. It really slows down your 7.3L in hills:

http://www.ford-trucks.com/forums/11837 ... st15833588

1der · 12-01-2015, 08:16 PM

Ramsey: still looking at 3.55 LS

Last night drive back from Long Beach, oaded up an extra 400 lbs of stuff and the 7.3 di not care about it at all. Driving all over AZ, we were doing 60 to 65 mph since my bro in law was towing a trailer behind his truck. The 7.3 was turning 1600ish rpm which felt a bit below the lower band when we hit a hill. At 75 mph, was around 1950 rpm. So, I feel the combo of 3.55, 285/70-17 will work fine for us since we are not towing.

3.73's would likely still be pretty nice for the type of driving we do. But would have to change front axle as well.

Btw- the TTB was super comfortable on the whole drive. There were two instances where it really got my attention - both doing about 75 and did not see the deep dip in the fwy that I fully expected would bottom out, suspension and shocks just soaked it up!! I was bracing for the bammmm, it never happened!!! Love the TTB!!