Leithus

I am going to be picking up my dream truck from my old boss soon. It is a 1993 f150 with the 4.9L and a 5 speed manual. No mods on the truck. I was wondering how this truck will do at interstate speeds? I need to drive it back to Montana and will be doing over 80MPH through Montana. Will this truck be able to handle it fine? What kind of RPM can I expect when I get into the 80MPH range? I heard there was a speed limiter on the truck at 90MPH, which is probably what I will be driving at if possible. Anyways if you guys could let me know an estimate RPM for driving over 80MPH with a 5 speed that would be great.



This is my future truck

frank5079

I have a '95 with the 4.9 and 5 speed as well; the only mods I've done was change the rear end from the original 2.73 to a 3.55(the 2.73 started clunking and making noises as well as spewing out gear oil) which I like better, and I got a 120mph Lightning speedo cluster. As to your question about the speed limiter, yes that kicks in at 95mph(which is about 3200rpms on my tach....

memoniz

I have a '96, 4.9, Auto. and I would not think of driving that fast for any length of time. My truck does not have a tach so I really don't know the RPM at that speed. It's not that I don't think the engine could handle it, I would wonder about the rest of the truck. Besides, the gas mileage would be terrible. I would get to know the truck before I pushed it that hard.

frank5079

If I drive combined highway and city, I get about 14mpg. Strictly highway at 65 to 70, about 16mpg. When I leadfoot it, I get about 13-14mpg, and that's 85 to 90mph.

memoniz

Mine used to be that way until I got bigger tires.

unit505

21mpg at 55-60mph. Drops pretty quick above that, but I can still get 17 at 75. Warm air intake, electric fans, synthetic fluids front to rear, stock tires, 2:73 rear. The 2:73 is the highway gear. Best mpg in the 9th gen category. I've had mine up to 100 one time and no speed limiter kicked in, except for my foot getting nervous!

Junkyardjeff

I had the same motor and trans in a 95 beater and drove it 70 to 75 on the highway with no problems even with over 250,000 miles,I would probably still have the truck if the frame had not got very rusty going through all those Ohio winters.

andretti05

I have the same truck, doesn't really go past 80. It has some suspension/steering issues so it rattles past 70 pretty bad. I keep her at 55.

clintm6

I have the exact same setup as you, including the K&N, dual fans, same gearing, but can only manage between 18-19 at 60 mph. I have a hotter coil, plugs at about .065, but just standard fluids. New stock size tires too! The only upgrade I haven't done is the 3G alternator. Would that make any difference in the MPGs?

unit505

I'm not sure about the alternator upgrade, but I do think that more juice should feed the ignition system better. I may be totally wrong, but it can't hurt. Do you have the manual or automatic transmission? I know the manual does get slightly better fuel mileage. Also keeping a fresh fuel filter and make sure that your pumps are in good shape and delivering fuel properly. Against every post on every site, I run my tanks dry regularly. I always keep a full tank and run the partial tank dry until the truck dies. I hit the selector switch and swap tanks. When I got the truck, that was the first thing that I did to make sure that I got all of the trash out of both tanks. The truck has both original fuel pumps and 200k miles and I've changed the fuel filter once. Other things that I do are standard motorcraft copper plugs, factory wires, factory coil, cap and rotor. I've seen good reports on the hotter coil and I've seen other users get better mpg with factory ignition components. At 200k, I've decided to keep my factory coil so I don't risk hurting anything.