Well after @Sous tested the 363/68 towing 'heavy' with great success, my own curiosity got the best of me. I ordered a 363/68 back in April and was able to install it in the middle of July after waiting on backorders, a damaged turbo and poor customer service. Also, thanks to @ESwift @RacinJasonWV @SRBF150 for going against the grain from what has historically been tried and true in the 7.3 SXE world and trying a ‘smaller’ turbo.

Over the next month and a half, I put roughly 100 miles on the turbo. Initially, I wasn’t impressed. Not that the 363/68 wasn’t good but because of 1) where I live the terrain is pretty dang flat (North Texas) 2) my tire/gearing combo gets my truck moving very quick requiring very little fuel. These two things made the 364.5/74 a non-issue for daily driving. So, unloaded and on flat ground, I don’t see amazing low-end boost with the 363/68 and thus when compared to the 364.5/74.91 I didn’t see much of a difference at all.

However, having been down the turbo path before and having a solid understand of what drives the turbo (fuel makes heat, heat drives turbine, turbine drives compressor etc) I knew I needed to hold off with any reviews until I could get the trailer hooked up.

On Sept 1st, we left North Texas on a 2600 mile road trip up to Wisconsin and back. The 363/68/.91 did amazing. While I can't or won’t compare it to the 364.5/74/.91 because last fall I did a gear swap from 3.73s to 4.30s in an effort to help overcome 35 inch tires, I can share the following details on how the 363/68 preformed:

With a load, the 363/68/.91 is an instant boost builder. 1400 - 1500 rpms, the turbo is lit and connected to the go peddle. Towing at 65MPH and 2000 RPM, EGTs ran 800-900 on the flats, slight to medium inclines would push EGTs to 1000 and 1100 if steep long enough. I found it extremely hard to pull any hills at 65 as the truck typically would continue to gain speed. More often than not, I was pulling hills at 70 and passing. For anyone wondering, I run the PHP 80HP TNAA4S2 tune.

There were a few instances I hit 1200 degrees but the EGT gauge just hit a wall no matter how hard I pushed the go peddle. We hit one hill I wasn't ready for and ended up just clicking OD off and ran 60 and 2500 RPMs. EGTs were a cool 1000 degrees. Typically boost on hills was 15-25 PSI. I saw 30PSI on one hill but was pushing it pretty good yet still could not break 1200.

Running around unloaded in Wisconsin where there are many more rolling hills then in Texas, I instantly saw the benefit of the 363/68/.91 as a daily driver. All in all, I was very impressed with the 363 towing in all situations. I was also very very happy with the swap to 4.30s which put my final gear ratio right between a stock 3.73 and stock 4.10 truck. My only annoyance was when getting on the highway, the truck would shift to 4th at roughly 52 MPH and RPMs would drop to 1600-1700. However, this again is where the 363 shines and would build boost instantly and pull strong to 65MPH with zero EGT issues.

I did not do any logging with Forscan but did see a nice 1.5 MPG bump in fuel mileage with the 4.30s vs the 3.73s. MPG netted out at 10 which I suspect is a little low due to two back to back days driving into 20 MPH head winds.

Below are a few pictures. The fifth wheel is 9,500 empty per the sticker. Add in water, fuel family packed 'stuff' and we are pushing 12K pounds.



65MPH @ 2000 RPMs, the truck was happy and so was I. Absolutely love having deeper gearing @SkySkiJason


This was what I would typically see pulling nice long mild interstate inclines.

 

Good and informative review! Glad the 363 has worked well for you also. Gearing is the mechanical foundation and must be addressed or understood at a minimum when going with 35's. The combination you have now sounds ideal.

With 160/30's, I can get past 1200* if I lug, but with rpm, all is good!

 

Glad to see you are happy with it. Thanks for the in depth opinion. You certainly gave it a good amount of road time to get a feel for it.
4.30 gears certainly help lots towing, I am liking my 363/68 with 4.30 and 32" tires with my 4r100 a lot.

 

Aaron, we are very pleased to hear you have gone public with your impression after quite a while of gathering your thoughts on the swap.

I bet if you had not had the 20 MPH head wind you would have been close to 12 MPG's towing the 5th wheel. Combined with your auxiliary tank, that is a great amount of range.

Thank you for taking the time to formulate a well thought out review with facts, numbers and pictures of course.

I look forward to seeing your family and setup the next time we roll through north TX.

Lastly...

 

Hey Aaron, glad to hear it’s working out for you!

I think your gearing choice is a big part of the equation. It should help you spend less time in the potential ‘dead zone’ rpm and also be really beneficial during towing. You built a great foundation which likely translates into an awesome truck.

To be honest, I think a big part of why I continued searching for “my best setup” was due to the small plenum leak that I eventually found. It was just recently sealed and I feel like the setup is even better now (duh). The truck just feels so strong with its current configuration. (Can’t imagine how well it would tow with lower gears!)
My point is, the little bit of boost leak was enough to make the 364.5/73 not be a good match for me. The leak likely exaggerated the slight turbo oversize for my use and forced me to keep looking for something better suited to my needs. Had my plenum been properly sealed I would have just learned to drive it and we may never have arrived at this experiment. Lucky accident or dumb luck? lol

I’m very happy that you are enjoying the new setup. Hope it gives you many miles of smiles!

Thanks again for all your help when I was installing my T4 kit.

 

akcooper9 I'm a little late to the party ,but thanks for the review. This gave me a little more real world experience from someone in my neck of the woods (just southeast of Dallas). I don't have any experience other than a stock turbo, but of course was curious between the 364.5sxe and 363sxe.
Info much appreciated.

 

Your welcome
Where are you located? I'm in Alvarado. If you want to go for a ride in a 363 truck and 364.5 truck let me know

 

This was with stock injectors???

 

Well now there's an offer that's hard to turn down. I ordered a 363/68 but it is on backorder. I have the .91 housing just not the supercore ,but I'm on 285/75/16 tires and 3.73 gears.
I'm about an hour away from you and know your area a little. Used to live in Fort Worth and worked in Venus and Cleburne doing pipeline work back in 2008. Kerens is where I am now. Small town just east of Corsicana.
I'm a new member here so I don't know if I have posted enough to private message yet. I have no problem driving to you or meeting you somewhere. Your preference. That's a great offer and would like to take you up on it. How do we proceed?

 

Yes sir!

10 characters

 

Make your ten posts and send me a PM with your number and I give you call

 

Will do.

Thanks

 

@DAWEST , Aaron is a great fella to be friends with and his family is very kind and generous. All of that aside, you have a good ride ahead of you when you get into the 363/68/.91 turbo powered truck.

Below is a link to my most recent experience towing with the SXE. We look forward to your thoughts and impressions of the "ride" and the inevitable outcome.

Link: https://www.ford-trucks.com/forums/1...l#post20123789

 

Glad you are even more happy with the new setup Aaron. I just "finally" installed my 4.30's. So I'm still going through the break-in period now. It isn't the SXE, but I'm hoping this combination KC 63/68 and 4.30's yields some positive results....

 

I suspect it will and you will be happy. The mechanical advantage of the gears with greatly take the load off the engine and put the rpms in a better zone for towing. Looking forward to hearing how you like the gears.