I got an 89 f150 with the 4.9 liter staight 6 in it. I no this motor is torquey and its a 4 speed with a granny gear so it is geared low, but now i only have 33's with a couple inches lift. Anyways i was wondering if anyone has or has seen a truck with the same motor turn 36' or even 38's. And yes I no it would be more stress on the truck but it sees mud every other day anyways.

P.s I figure I've seen plenty of 4.6 and 4.7 turn those tires and the 4.9 has more torque than them.

 

oh yeah it will turn them...but how much stuff do you want to break doing it...

 

yes they can turn them fine, my friend has an 88 with 42's and its fine.

only mod is the lift and 1 ton axles

 

turn yes roast possibly break somthing definatly. regear the rear end and you should have know problems

 

The 300 doesn't make more torque than a modular V8 of any kind.

The 300 is underpowered and slow. It doesn't have the power through the power band to really be a mud eating beast with super swamper's. You really need a big V8. The most you can do with tires that big and the 300 is walk and crawl through mud. This is not always ideal.

You need to swap out your axles and get some 1 ton axles or better, and re-gear your truck something like 6:1:1 or lower.

I think it's cool you want to keep the I6. It's a great motor and I love to see it in rigs with massive tires. A lot of members on this site run 35's with their 300's. I run 31's with a 4.11 gear ratio. My truck is a pig. Runs good down low though.

By the way, I have no experience with large tires with the 300. My 300 is backed by the E40D and that sucks down some power. Reguardless, I've been driving my truck for the better part of five years and from everything I've read on this site... You're just asking for trouble. You're going to roast your motor.

By the way, do you have a tranny cooler?? I would look into beefing up your coolant systems.

Just my $0.02. Again, I think it's a really cool idea and I honestly hope you go for it; I just want you to realize you're asking for trouble.

 

Bill, why would he need a tranny cooler with the 4-speed? That ain't no NV5600 or something equally beastly that runs on ATF and has its own oil pump.

To the OP - regear your truck to 4.56 and you won't break driveshafts, but you will break axles if you push the truck too hard. Install a D50 stub shaft in the D44 TTB cause the factory part will be the first to go. 36" is as large as I'd personally go with halfton axles.

 

Brain fart. I'm used to my automatic getting hot.

 

I'm gonna run 37's on mine someday, but run a chrysler 9.25 rear, as it already has 4.56's and a limited slip, and only 16k miles. To keep the front alive I'm gonna run warn hubs and warn hub fuses, which are plastic gears inside the hub that'll strip before an axle could snap.

Right now I got 35's, 3.55 gears, a 4.9 and 5-speed, and OD is a dog on highway hills, and steep hill starts are a bit tricky with the higher-geared 1st. But plowing and tough off-road stuff are done in lo-range so there's no shortage of power and the slower speeds mean less beating on the truck.

 

Good post, waynaferd. I'm repping you for the honest report.

waynaferd pretty much sums it up.

Get some serious GEARS and the right axles and you'll be able to turn'em. You won't have any real power and your fuel mileage will suck, but your truck will sure look good at the mall!