Running in 4th
Thread Starter
|
Posting Guru
Joined: Jan 2003
Posts: 1,507
Likes: 0
From: Magrath
Running in 4th
Just a simple question. In 4th gear at 70mph, my truck sits at 2500 RPM's. In 5th @ 70mph the truck is at 2000rpm's. However, the truck doesn't seem to have any power (can barely pull itself up the hill) in 5th gear. The other thing I have noticed is in 4th gear, the throttle sits about half way. In 5th, the throttle sits 3/4 or more.
My question is, will it hurt to run the truck in 4th and quit using 5th gear all together.
My question is, will it hurt to run the truck in 4th and quit using 5th gear all together.
Junior User
Joined: Apr 2003
Posts: 73
Likes: 0
From: Coos Bay, Oregon
No, it wont hurt anything. Your mileage shouldn't suffer either, if you've had to stuff the throttle even more to run the same speed in OD (which isn't good for mileage). Don't worry if you can't pull hills hard in OD, it wasn't designed for that. 2500 RPM @ 70mph isn't very bad at all, actually. My truck turns about 3k going 70 in 4th.
Laughing Gas
Joined: Jun 2003
Posts: 1,218
Likes: 2
From: Parkville, MO (KC)
You fellows have too high rear differentials for a truck with a 5 speed OD. You'd get a lot better overall performance and maybe even better gas mileage with a 3.25 or even a 3.5 rear.
Just my $.02
Just my $.02
A mostly quiet Supporter
Joined: Jun 2003
Posts: 249
Likes: 0
From: Lansing, IA
My 95 with the M5OD 5spd and 3.08 rear turns about 2000 rpms in 4th @ 60 mph. Where I live it is quite hilly and if I am not on the interstate (or going less then 70), I tend not to use OD (5th).
So staying out of OD unless:
-over ~70 mph
-driving on really flat terrain
Makes the most sence to me
my $0.02
T. J.
So staying out of OD unless:
-over ~70 mph
-driving on really flat terrain
Makes the most sence to me
my $0.02
T. J.
Last edited by the_webers_inc; Dec 4, 2003 at 10:36 PM.
Trending Topics
Posting Guru
Joined: Apr 2003
Posts: 2,123
Likes: 2
From: WA
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Freshman User
Joined: Jul 2003
Posts: 48
Likes: 0
From: alaska
i got a 4 speed with the 3.08s too. I think i might change the gears to 3.5s or 3.73s. I got 35" tires on it with a 6"lift so I think ill have more power up hills and better high end power. And with the big tires it shouldnt rev up the rpms too much.
Senior User
Joined: Jun 2003
Posts: 390
Likes: 0
From: Rose City, MI
i have a 4 speed and 3.08s and i never use 4th unless i am on a open road and doing 60 or better. I am thinking about getting a 3.55 or 3.73 rear since i do alot of city driveing....... or maybe a tranny swamp..... havent decided yet. no tach either so i couldnt tell you how many r's i'm cranking in 3rd at 60......even though i can max the spedo with half a pedal in od imho the 3 speed od tranys are JUNK unless you are only cruising at high speeds with no loads!!
Last edited by 85F_150driver; Dec 7, 2003 at 01:37 AM.
Elder User
Joined: Jul 2003
Posts: 997
Likes: 0
From: Weston, Nebraska
If your running 60 in 3rd with the T-18 4 spd, then your running about 3900 to 4000 rpms. I only run mine up to 55mph. But yours says 4spd TOD, I'm not sure what that is. I can dive mine up moderate hills in 4th gear at 30 mph and it'll lug right up them, I sometimes just cruise around town in 4th.
Redneck-Cowboy
Redneck-Cowboy
Senior User
Joined: Jun 2003
Posts: 390
Likes: 0
From: Rose City, MI
from what i have read the TOD tranny is a single rail od with a top mounted shifter, i am thinking bout steppin up to a zf-5 but i dont know how well it would bolt up to my 85 anyone got some insight on that??
Junior User
Joined: Apr 2003
Posts: 73
Likes: 0
From: Coos Bay, Oregon
I forgot to post the specifics of my drivetrain. Along with my ZF tranny, I've got stock size tires and 3.55 gears. My truck can pull over 75, 80 mph without too much trouble. Falls on its face on big hills though.