Also what kind of speeds are you guys able to hit on a freeway. I'm about to do a "speed test" hahaha
Last edited:
FJ40 on a freeway? (1 Viewer)
- Thread starter BroderickDover
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
1911
chupacabra
Depends on your diff ratio, tire size, and the health of your engine.
With stock (for me) 3.70 diffs, healthy 2F (though carb secondary inoperative), and 33" tires, I can do 65 mph comfortably all day. Will do more than that, 75 on a flat road, but I don't like to rev it that high for very long and the steering of anything with this short of a wheel base gets scary at high speed too.
With stock (for me) 3.70 diffs, healthy 2F (though carb secondary inoperative), and 33" tires, I can do 65 mph comfortably all day. Will do more than that, 75 on a flat road, but I don't like to rev it that high for very long and the steering of anything with this short of a wheel base gets scary at high speed too.
I decided at 95 mph, that it was the highest I'd want to go... When it was still accelerating and showing no sign of topping out... 
60-65 is a nice top speed... It'll do more, but safety with a short lifted vehicle is a consideration.
60-65 is a nice top speed... It'll do more, but safety with a short lifted vehicle is a consideration.
70 mph on 4.11's and 31's for hours. It's about 3200 rpm so the motor is humming, but the old F did it reliably multiple times. I used to go faster with 33's and 3.70's. Basically, I went the speed limit wherever I went.
reddingcruiser
Practicing for retirement
I do 75mph all the time on the Interstate. Could also go faster, but emergency high speed maneuvers and FJ40 usually don't occur in the same sentence.
- Thread starter
- #6
Stock diff ratio
35" tires (all terrains)
Engine health: somewhat of a Frankenstein swap. But in the last few years I've given it good care. Id say it's good
35" tires (all terrains)
Engine health: somewhat of a Frankenstein swap. But in the last few years I've given it good care. Id say it's good
4.11 gears, 283 V8, 4-speed transmission and 31 inch tires - The truck will do 65 at about 3000RPM. The V8 is capable of revving higher but honestly, as others have said - short wheelbase, high speed, and the aerodynamics of a brick acting like a "sail" in windy weather all make driving at "normal" interstate speeds (70-80mph) a little unnerving. I stay in the left lane and do 60-65. Frankly, the big mechanical fan on the 283 is so loud at 3000rpm it makes too much noise to go much faster! Just based on max RPM of the 283 and driveline components I imagine I could probably do 80, I just don't want to.
It also takes me a full 20 seconds to hit 60, if I'm trying really hard. Driving a tall, short wheel base truck around a sharply curved/banked freeway onramp while attempting to accelerate to highway speeds is a harrowing experience!
As you can probably imagine, I stick to back roads.
It also takes me a full 20 seconds to hit 60, if I'm trying really hard. Driving a tall, short wheel base truck around a sharply curved/banked freeway onramp while attempting to accelerate to highway speeds is a harrowing experience!
As you can probably imagine, I stick to back roads.
JohnnyC
Long ago TLCA# 2231
20+ years DD the same truck it drives fine on the hw ... As others said 65-70 easily ... I have gone faster ... My previous DD 's were a 79' full size Cherokee and before that 73' triumph ... I was 2 points from loosing my license lol ... I wanted something that would force me To go slower
I have a V8, 35s, stock 4.11 gears in the axles. I don't know what my "top" speed is, but I cruise at 60-65 on the freeway. I feel more limited by comfort of handling a SOA short wheelbase FJ40 at that speed then I do by the engine/gearing. At 60 it feels very comfortable and controllable. As I start passing 60 I feel less and less comfortable in how it handles and feels overall. Also.. the noise becomes significantly worse over 60ish.
A 40-series short-wheelbase is too skittish (mainly due to its high centre-of-gravity and short-wheelbase) to safely sustain speeds over 110 kph IMO.
80 kph (50 mph) is what I like best if I'm not wearing ear muffs, want to enjoy "the relaxed mechanical hum of finely-engineered classic vehicle", and if I have no banked-up traffic behind..
80 kph (50 mph) is what I like best if I'm not wearing ear muffs, want to enjoy "the relaxed mechanical hum of finely-engineered classic vehicle", and if I have no banked-up traffic behind..
Pretty much like the rest. 31/10.50's, 4:11 gears, stock 2F , 55mph all day ( actual speed at 55 indicated is about 60 mph according to GPS) @ 2500 rpms. Have gone faster when needed, but sounds and feels good here.
I have a stock 4.11, 2F, 30s and can cruise at 65mph and 3200RPM.
But, as @reddingcruiser said... "emergency high speed maneuvers and FJ40 usually don't occur in the same sentence." and @FJ40Jim said, "...anything above 2600RPM with a 2F is just turning gas into noise".
As @JohnnyC said, "I wanted something that would force me To go slower ".
I'm retired, I have no place I need to get to in a hurry and I love to see what I can see... so, I try to drive at 55, but sometimes catch myself inching up to 60 and immediately drop back down.
But, your question was "...on the freeway..." - on the freeway, I feel as though I'm parked...
But, as @reddingcruiser said... "emergency high speed maneuvers and FJ40 usually don't occur in the same sentence." and @FJ40Jim said, "...anything above 2600RPM with a 2F is just turning gas into noise".
As @JohnnyC said, "I wanted something that would force me To go slower ".
I'm retired, I have no place I need to get to in a hurry and I love to see what I can see... so, I try to drive at 55, but sometimes catch myself inching up to 60 and immediately drop back down.
But, your question was "...on the freeway..." - on the freeway, I feel as though I'm parked...
Flat land, she'll go as fast as you want, on a hill, you'll slow down. For me, it's how much pain I want to put my ears through, ear plugs have made long rides comfortable, and the radio easier to hear. Actually the road noise and wind is the loudest probably over 55mph.
^This is like worrying about the water-fording ability of a Mustang. The less the better.
Indestructible 47
SILVER Star
for what it's worth, a 2H in a ute (not loaded and my cousins) rekons he could pull 135-140 (86 miles), but I know that engine is well maintained and that he isn't the worst driver although, he admits he won't be doing it again anytime soon.
shipmag
Hagler Technology LLC. Aka Shipmag
stock 4.11 dif 31 inch tires 55 is the max I will go with a stock 2f. Tried 70 MPH and blew the engine. Nice white smoke blew out the tail pipe. So lesson learned these rigs aren't made for engine speed much over 3,000 to 3200 RPM. So depending on what difs you have will determine your speed. I can only speak of 4.11 never had 3.70 in an FJ40. If you want to do 70 flat tow it behind a more modern truck with some power. Coolerman makes a flat towing harness for the FJ40. A special adapter has to be used when going from a 4 wire system to the FJ40 5 wire system. He has posted this on his thread here on mud.
