Last night,we went off-roading in my 1/2 ton with a I6 to power it,shes still stock,so when we got to the end of the stirp we was running down,(wasnt that long) i noticed the engine ran kinda rough. guy next to me said he thinks he saw a spark,but i doubt it,he was really relaxed at the time,lol. anyway,i cut the engine off,and cranked it back up,ran just fine. How tough are these engines? And what about the C6 trannys?

 

In my personal opinion, the 4.9L (300ci) I6 was the best overall engine Ford ever produced. They are amazingly durable, and will outlast the truck they came in. The most common problem they have are dirty injectors. For some reason, just about every EFI 4.9L built will eventually have to have the injectors cleaned, and or replaced. Typical symptoms are a slight miss at light throttle, while cruising between 35-45 mph. It will clear up under load, but will return when cruising that speed at light throttle again. Eventually, if left untreated, the truck will develop a bucking, surging issue just off idle. It will feel like the truck is out of fuel.

I prefer the 5 speed tranny, but the C6 is an excellent transmission, as far as Ford automatic trannies go.

Take care,
~Chris

 

I have to agree. If you take care of them they are easily 250K mile motors and I have seen them go even more. The best part is they get better millage than the 302's did and certainly had more backbone than the 302. They are indeed really tough little engines.

 

My only problem was I couldnt get mine to blow up without being obvious.

 

The 300 six will last forever. You can literally beat the hell out of it and it will come back asking for more. Had one in an 85 Bronco with the 4 speed granny first. Didn't matter if it had regular maintanence or not. Awsome torque down low. I think it had a peak right around 300 ft.lbs at 1800. Might be off on the numbers a little, but not much.

 

Ive been doggin this one kinda hard lately though. Damn,between the C6 Tranny and the I6,i got one bad setup,lol.

 

The only thing to remember about that engine is that there is absolutely no need to over-rev it. Like Troton_Motors said, the torque output is REALLY low. I had one in an 88 F150 with the 5spd. I can't tell you how many trucks and SUVs that thing pulled off the beaches of North Carolina. What you haven't gotten out of it at 3000 rpm is not going to be had---so don't over-rev it and you'll be driving that thing for a LONG time. I still don't know why Ford stopped making it---spare parts sales were not sufficient I guess!

Sidewinder

 

i agree the 300 straight 6 is great. the C6 is indestructible unless you tear the transfercase and tranny out on a big rock. (talking from experience)

 

You just described my truck in a very shallow manner. I will have the Engine speed at Idle drop, and won't be able to rev any higher than 1200 until it clears up. I've always had that slight miss at idle, very light load. I have had the injectors cleaned with a fluid, but never physically removed from the rail....

 

On average,do they get good fuel milage?

 

How much should it be to have someone replace the injectors? How hard would it be to do myself? TIA.

 

4.9L engines get pretty crappy mileage.

Replacing the injectors is a 2 hour job if you're experienced. If not, it could take the whole day, I suppose. You have to remove the upper half of the intake manifold.

Guitar_Stitch-
You may also be having an EGR problem. Try disconnecting and plugging the hose to the EGR valve, and see if that makes any difference. If not, you can try cleaning the injectors the easy way; Go to Kmart, and in their automotive section, find their fuel system additives. Get about 60 ounces of whatever brand you like of fuel system cleaner (I prefer the one in the gray bottle with the copper colored cap, in about a 32 ounce bottle (I get two), because it's the cheapest, and it works).

Get one of your gas tanks near empty, and go to the gas station and pour 60 ounces of that stuff in the tank (disregard what it may say on the bottle), and add 5 gallons of gas (NO MORE than 5 gallons!). Drive it around for an hour or so, and then park it for the night. The following day, you will notice a huge improvement if your injectors were dirty.