The Inevitable Comparison: GM 6.6 vs. Ford 7.3

kenny_r · February 1, 2020

Yea I mean over 3 minutes faster...pretty insane for not having that much more power

magnum74 · February 2, 2020

1 hour ago, kenny_r said:

Yea I mean over 3 minutes faster...pretty insane for not having that much more power

The 10-speed is a must for the 6.6 to be performance competitive. I expect the Ram 6.4 8-speed to beat the 6.6, not as dominant as the 7.3, but the extra gears on the gas engines make them work better. It is what it is. The fact that the 7.3 is achieving 15mpg in real testing makes it the one to beat although it is an extra cost option. I'd like to see the F350 6.2 10-speed compared to the the 6.6. I bet it beats it.

I don't tow 16K up the Ike but it's a pure torture test that exposes strength and weakness. I'm sure the added gears are not far off from GM but this was a sound thumping.

artie2908 · February 2, 2020

I believe the 7.3 has been getting 15mpg with the 3.55 rear end. In the mid 14's with the 4.30's. On the Ike test that 7.3 had the 4.30 rear vs 3.73 for GM. Sure the 10 speed helped greatly but the Ford also had a distinct advantage in rear gears. Overall interesting to watch but in the real world who is towing that much weight up a grade like that. I bought mine to tow 7,000 lbs and the 6.6 gas will be just fine.

C/K Man · February 2, 2020

I agree, most of the 7.3L's advantage is attributable to the 10 speed transmission and 4:30 gears. Which leads to the question how would the L8T be with a 10 speed transmission and similar gears.

C/K Man · February 2, 2020

Particularly for you LS fans, take a good look at these Ford 7.3L videos:

2016HD · February 2, 2020

Sorry I dont believe that the 10 speed will make that much of a difference? 4.30 vs 3.73 is more the deal maker. However a 3 min change? Something is not quite right there? Sorry but the HD diesels were just compared and the Ford has 140ftbls more than the Dmax and Barely bested the Gm in time. A minute difference i believe. I think Mr truck Or should i say mr Ford needs to stop doing the driving! The 7.3 isnt putting out that much more power. Either traffic or other issues were involved. Just my thoughts. But lets see how the durability is? Almost a copy of an LS engine as well. But Hey thats a compliment from Ford. LOL. Just my thoughts

kenny_r · February 2, 2020

I remember them testing the ford 6.2 hauling 12k and it did in like 8 minutes. Of course it broke the first test, but the second run hauled ass. So a lil longer for 7.3L, not much. more gears, 4.30 ratio, bit more power and 4K extra pounds, I think they kept it a clean run.

Colossus · February 2, 2020

well I admit it. I am getting old. All this time I was thinking this topic was regarding some brand new diesel engine that Ford had come out with vs the latest Duramax. ::face palm::
:idiot:

magnum74 · February 2, 2020

12 hours ago, artie2908 said:

I believe the 7.3 has been getting 15mpg with the 3.55 rear end. In the mid 14's with the 4.30's. On the Ike test that 7.3 had the 4.30 rear vs 3.73 for GM. Sure the 10 speed helped greatly but the Ford also had a distinct advantage in rear gears. Overall interesting to watch but in the real world who is towing that much weight up a grade like that. I bought mine to tow 7,000 lbs and the 6.6 gas will be just fine.

Not ragging on your choice, either. The 6.6 is a nice upgrade over the 6.0's I'm used to driving and I'm still fine driving mine today. In the end, it needs to be reliable before winning a race.

artie2908 · February 2, 2020

agreed. One of the main reasons I bought a new 6.6 gasser. Reliability. I have a 2011 Crew Cab 4x4 LML that I used to pull a 34 ft 5th wheel that weighed 11,500 lbs . Pulled it just fine. The only problem I ever had was with the emissions. I'd be on long trip and I'd get a CEL come on. A bad nitrogen sensor. That's great... now what. It will start going into a limp mode in 1,000 miles and I'm 1,300 miles from home. I've gone through 3 nitrogen sensors, one DEF tank, EGR code has flashed a few times but thankfully cleared. It's all been warranty but that's expensive stuff. Now add the potential for the CP4 problems and a lighter bumper pull trailer (7,000 lbs) --- a new gasser was the choice. I did drive the 7.3 before deciding on a 6.6. Ford was nice but I think power seemed very similar. I thought the 6.6 shifted a lot smoother and felt more refined. I would have been happy with either one. JMHO

diyer2 · February 2, 2020

I think this towing up Eisenhower is foder for the maases. If it impresses you, great !

Me, not so much.

They use the time it takes to pull this grade as a measuring stick. Not applicable in the real world IMO.

Most people buy a truck to haul things or tow a trailer. Whether it be a TT or a trailer for work or farm.

They will never see the gauntlet. Most will not race their trucks either.

As artie2908 said - In the end, it needs to be reliable before winning a race.

I live in Colotado and have pulled the gauntlet in many different vehiles. Cars, trucks, motor homes. Towing and not towing.

I have been the one getting passed and the one passing.

In the end, getting to your destination trouble free is the goal IMO. So if it takes a few minutes longer, so what.

If you drink the Kool - aid of this test what are the benefits.

i82much · February 2, 2020

direct injection enabled a higher compression ratio because you can inject the fuel later in the combustion cycle.

FirstAscent · February 2, 2020

They will never see the gauntlet. Most will not race their trucks either.

I live my life 1/4 gauntlet at a time. Haha

Yeah I will 99.9% never tow the gauntlet or even drive through it, nor will I be towing that much. These tests wouldn’t sway my decision one way or another but I still enjoy watching them for comparison even though it’s not a realistic scenario for most of us.

I’m happy with my choice to go with the 6.6 duramax.

artie2908 · February 2, 2020

1 hour ago, FirstAscent said:

I live my life 1/4 gauntlet at a time. Haha

Yeah I will 99.9% never tow the gauntlet or even drive through it, nor will I be towing that much. These tests wouldn’t sway my decision one way or another but I still enjoy watching them for comparison even though it’s not a realistic scenario for most of us.

I’m happy with my choice to go with the 6.6 duramax.

in the end..... that's all that matters. It's your truck and it only has to make you happy. ok- maybe the wife too. LOL

Ray Pickle · February 3, 2020

Comparing TFL times up the Ike gauntlet 7.3 vs. 6.6 is not about the engines at all but about transmission tuning choices. The 7.3 ran much closer to its horsepower peak the majority of the run staying between 4200 and 5k for almost the entire run. GM allowed truck to follow more of an economy strategy thus having engine turn between 2600 and 4k way too much of run. Clearly no one with any towing experience would ever so that. I get why they do it for uniformity in testing but it does not offer any insight into real world performance.