Let me know if this is not the right place for this. It's going in an F700 but I figured this was the place to ask about the 6.0.

So I have a 1976 F700 that I've been thinking about engine swapping. It's got a gas FT 391 in it right now. I go back and forth about what engine to use. It's hard. I feel like there are really great semi engines out there for cheap (in relative terms) and good light duty engines out there for a little less cheap, but no cheap medium duty engines that fit my bill. I think I've finally decided. I'm on a bit of a budget here. Then it hit me. What makes an engine cheap? Undesirable qualities. What if there was an engine that could be perfected with a little work that others wouldn't want to touch? What's a super underrated engine that comes with flaws that can be easily remedied? What's an engine that can provide a good amount of power when you really lay down the boost?

The 6.0 powerstroke.

I don't have tons of cash, but I do have enough to hop up and bulletproof a 6.0. And yes, I do feel like I need to lay the boost on a little; nothing insane, but this is a heavy truck that is going to be doing heavy truck things. I think stock power would be unsatisfactory. This is why I never considered (for very long) until now a lighter duty truck engine.

Anyone have experience doing a more performance based build on a 6.0? How did it go? How much power did you get out of it and how? Also, what am I not thinking of here? What's the great gaping holes in the plan? Anything you all want to add is welcome.

 

I would honestly just put a CAT 3176 with a manual transmission behind it. I've driven in and rode in service trucks that have them paired with 10 speed Eatons and they can get up and go with 20,000Ibs behind it. The guy I work with had one as his daily service truck and he got out of some reallyyyy sketchy spots using that thing.

 

While the 6.0 can be made to be very reliable, and really the most complaints came from people who just threw tunes on them and tried to get them to do more than they were built for...it's not an engine I would use for your application.

If you were looking for an undesirable engine to tinker with, you'll find a LOT more 6.4 powerstrokes, but I would avoid them like the plague.

I would, as stated above, look for a CAT or a Cummins to drop in. More reliable right out of the gate, less headache down the road, and parts are more available because a lot of them are still being built.

 

Related:
https://www.ford-trucks.com/forums/1...a-76-f700.html

 

I agree here and would also advise against if your looking to work this truck regularly and rely on it. The 6.0s (customers and my own) that ive seen live a longer fairly trouble free life were those that didnt work hard on a regular basis. The ones that were always down for maintenance were the ones working every day usually close to or in excess of their intended limit.

Seek an older 8.3L Cummins is my advice. All mechanical, no emissions, and very reliable. Can get up to 275hp in stock form and with even a basic 6 speed manual behind it will easily outperform the 6.0L especially in medium duty applications.

 

Thanks so much guys. I didn't realize that the 6.0 wasn't a good work engine. I've also considered dropping in an 8.3 Cummins, I was just trying to find a way out of it because they're pretty expensive, at least, for a reman. I may just need to get an old used one. I've also considered dropping in a Detroit 6v92, those can be had for quote cheap in my area. Thoughts there anybody?

 

DT466 mechanical is another option. 3 or 4 variation of the mechanical version of that engine that are really reliable and solid workhorses.

6V92 Jimmy will do the trick also. If its not leaking oil it cant be trusted

VT365 (Navistar version of 6.0L) was offered in class 5 and 6 International chassis. Was rated at 230hp. I have absolutely no experience with this version but am real curious if it was more reliable due to 100 less hp vs the PowerStroke.

 

Personally I’d think tying in the 6.0’s electronics to that 70’s chassis would be a challenge in itself, but I’m not an electronics person
6V92 isn’t going to fit in a F series engine compartment
The DT466 and 8.3’s length will require a lot of firewall modifications
My 93 800’s 8.3 sets back in the cab around 4-5 inches
The older F-800’s were available with the 3208 Cat but the engine compartment was packed making any type of maintenance a challenge

Swapping in a diesel engine into an older gas chassis is just the start, there is no bell housing available to mate the trucks gas transmission to a diesel, plus that trans won’t handle the diesel’s torque for very long, so a transmission upgrade is necessary
Next is the rear axle that is geared to the the gas engine operating range, a 391 works best at 2700-3400 rpm with peak rpm of 3900. With many years of driving these trucks I can tell you they don’t like to be lugged down below 2400 rpm, this is near the peak operating range of most diesels so you’re looking at a max speed of 40-45 mph without a gear change
Higher speed gears for those older axles will be difficult to find if at all, plus the small 3/8 axle studs will eventually fail from the higher torque
Lastly is the brakes, if the truck had air brakes that great and it allows more options on swapping in a newer style axle
If it has the old style vacuum boosted hydraulic brakes with the single reservoir master cylinder, those brake systems were marginal even when new, replacement brake drums are near impossible to obtain today

I advise you follow the route of another member a few years ago and find a later model diesel chassis to swap your older body onto