2019 F350 6.2L 4WD build thread; HPI flatbed, ATO AterraXL composite camper, Carli/King, 37s, 4.88s, etc

[RAM5500 CAMPERTHING]

Gear drama... That's been my experience with aftermarket gears. Even done by pros. They don't last or have issues (and expensive). Hard to beat the factory 4.30s (for cost and lack of drama).

Hope you can get it sorted out!

I’ll strongly disagree with this all day long sir

I’ve had almost truck I’ve owned regeared (including once doing the work myself) and have not once ever had an issue or failure. My 100 series LC had over 100k on the regear.

Both Yukon and Nitro have been around forever and 1000s and 1000s of sets installed. They’re good brands.

With that being said, certain gear sets/ratios on certain vehicles just whine and it won’t go away ever, it’s the design.

Example, I know with the older Toyotas any brand of 5.29s will whine, it’s just how it is.

I know nothing about Fords and which gears run best, but I’ll agree with you that regearing from 430 to 488 is basically comical, for how minimal the gains will be vs costs. I’d go at least 5.29 if I was spending that $.

I went from 4.30 to 5.29 in my tundra and it was absolutely perfect with 35s. That doesn’t relate here, too many variables, but just a random dumb fact.

 

[Klutch7]

Thanks, @mk216v for such a well-documented thread so far. I am very close to my next F-350 order and this thread is helping me think through it! Appreciate all of your knowledge - I am also guilty of analysis paralysis. Every. Damn. Time.

Looking forward to the progression!

 

[mk216v]

I’ll strongly disagree with this all day long sir

I’ve had almost truck I’ve owned regeared (including once doing the work myself) and have not once ever had an issue or failure. My 100 series LC had over 100k on the regear.

Both Yukon and Nitro have been around forever and 1000s and 1000s of sets installed. They’re good brands.

With that being said, certain gear sets on certain vehicles just whine and it won’t go away ever, it’s the design.

Example, I know with the older Toyotas any brand of 5.29s will whine, it’s just how it is.

I know nothing about Fords and which gears run best, but I’ll agree with you that regearing from 430 to 488 is basically comical, for how minimal the gains will be vs costs. I’d go at least 5.29 if I was spending that $.

I went from 4.30 to 5.29 in my tundra and it was absolutely perfect with 35s. That doesn’t relate here, too many variables, but just a random dumb fact.

We'll see how the Nitro 4.88 rear sounds. To me it's worth the cost to try.

My truck came with 3.73's, so the bump to 4.88's will be the sweet spot for 37" tires I think. If I could have found a rig with factory 4.30's (very challenging to find in a pickup, even my chassis cab took time to find with 4.30's), then I would have stayed with them. But 4.88's will net me a bit more usable power, at the expense of some mpg. 4.88's BTW, are the lowest(highest numerical) offered for '11+ Ford SuperDuty.

We love your random dumb facts. Please keep them coming.

Thanks, @mk216v for such a well-documented thread so far. I am very close to my next F-350 order and this thread is helping me think through it! Appreciate all of your knowledge - I am also guilty of analysis paralysis. Every. Damn. Time.

Looking forward to the progression!

You're welcome! For all the years I've been perfectionizing (I know that's not a word) on this build, I'm glad I can help someone else reduce their analysis paralysis a bit.

 

[RAM5500 CAMPERTHING]

We'll see how the Nitro 4.88 rear sounds. To me it's worth the cost to try.

My truck came with 3.73's, so the bump to 4.88's will be the sweet spot for 37" tires I think. If I could have found a rig with factory 4.30's (very challenging to find in a pickup, even my chassis cab took time to find with 4.30's), then I would have stayed with them. But 4.88's will net me a bit more usable power, at the expense of some mpg. 4.88's BTW, are the lowest(highest numerical) offered for '11+ Ford SuperDuty.

We love your random dumb facts. Please keep them coming.

Ah…. I thought you had the 430s. Yeah, bumping up from 373 will be niceee….

 

[RAM5500 CAMPERTHING]

But 4.88's will net me a bit more usable power, at the expense of some mpg. 4.88's BTW

Huh? Half (maybe more) of the reason to regear is to GAIN MPGs, not lose them.

Used to keep track of all of them, but the last one i recall off the top of my head was the Tundra, regearing from 430 to 529 got me about 1.5mpg.

I recall my 80 series LC being an even more dramatic improvement with MPG

 

[mk216v]

Huh? Half (maybe more) of the reason to regear is to GAIN MPGs, not lose them.

Used to keep track of all of them, but the last one i recall off the top of my head was the Tundra, regearing from 430 to 529 got me about 1.5mpg.

I recall my 80 series LC being an even more dramatic improvement with MPG

Ah…. I thought you had the 430s. Yeah, bumping up from 373 will be niceee….

Will depend on the tranny and the sweet spot of rpm's, but in general as you know;
-Lower gearing(higher numerical R&P, ie my new 4.88's) will increase RPM's in a specific gear = more power on tap = typically this will not help increase MPG's.
-Higher gearing(lower numerical R&P, ie my stock 3.73's) will decrease RPM's in a specific gear = better for highway cruising = increase MPG's.

I'll log data and see what I get with 4.88's and 33" tires, then with 37" tires.

 

[john61ct]

Overdrive gear for flat highway cruising available on these models?

 

[RAM5500 CAMPERTHING]

Will depend on the tranny and the sweet spot of rpm's, but in general as you know;
-Lower gearing(higher numerical R&P, ie my new 4.88's) will increase RPM's in a specific gear = more power on tap = typically this will not help increase MPG's.
-Higher gearing(lower numerical R&P, ie my stock 3.73's) will decrease RPM's in a specific gear = better for highway cruising = increase MPG's.

I'll log data and see what I get with 4.88's and 33" tires, then with 37" tires.

Yeah, i worded my reply poorly.

Regearing to get RPMs and tranny shift points as close to stock as possible after a tire size change will increase MPGs, over leaving the lower numerical gears in there. Math might seem to make sense, but every aspect of the drivetrain is working harder when the stock gears are kept, and work = mpgs

My goal was always to get my trucks as close to back to stock as possible.

I use dis: https://spicerparts.com/calculators/transmission-ratio-rpm-calculator

 

[RAM5500 CAMPERTHING]

I'll log data and see what I get with 4.88's and 33" tires, then with 37" tires.

Also log data on the 35s you end up getting once you come back to earth and decide shaving a 37 is looney toons

[insert kissy face middle finger emoji]

 

[Mako1114]

This is a great build. Regarding the increased capacity fuel tank....does the ECU require some sort of update to accurately read the fuel level?

Cheers

 

[Skinhyfish]

Soooo… I just sold it, but I had a 6.2 Ford and regeared to 4.56 with 35’s. Nitro gears. Never had an issue for 45,000 miles. Nee owner stated he is running like a top. 4.88 is what I wish I had even with the 35’s with weight of flatbed and camper. Gear change was the best purchase for my build. My new diesel even got a regear. You will love the 4.88 gears. GWLB

 

[Skinhyfish]

Didn’t know if you also got the tires choose yet, but I just put in the maxis AT razor. Love them. Saw them in your list choice

 

[mk216v]

Overdrive gear for flat highway cruising available on these models?

Yes, there's an overdrive on/off button on the end of the column shifter. I often use this (ie turn Off) when approaching a steep mountain grade.

Yeah, i worded my reply poorly.
Regearing to get RPMs and tranny shift points as close to stock as possible after a tire size change will increase MPGs, over leaving the lower numerical gears in there. Math might seem to make sense, but every aspect of the drivetrain is working harder when the stock gears are kept, and work = mpgs
My goal was always to get my trucks as close to back to stock as possible.
I use dis: https://spicerparts.com/calculators/transmission-ratio-rpm-calculator

Also log data on the 35s you end up getting once you come back to earth and decide shaving a 37 is looney toons
[insert kissy face middle finger emoji]

Copy on stock gears + bigger tires = work = mpg lots.
No 35s for this rig. If I need to get a 37" spare to more easily fit in the spare tire well, I'll just buy a 40% used BFG K02 as I know it'll fit per @montypower.

This is a great build. Regarding the increased capacity fuel tank....does the ECU require some sort of update to accurately read the fuel level?
Cheers

Thx. Great question. Using Forscan, you can tell the rig that it has a 60gal tank (there are other pre-set choices);
https://www.ford-trucks.com/forums/1649945-forscan-threads-and-resources-index.html
Cell 45A in the Google sheet; 30/34/40/48/50/55/60/68/70gal.

Soooo… I just sold it, but I had a 6.2 Ford and regeared to 4.56 with 35’s. Nitro gears. Never had an issue for 45,000 miles. Nee owner stated he is running like a top. 4.88 is what I wish I had even with the 35’s with weight of flatbed and camper. Gear change was the best purchase for my build. My new diesel even got a regear. You will love the 4.88 gears. GWLB
Didn’t know if you also got the tires choose yet, but I just put in the maxis AT razor. Love them. Saw them in your list choice

Thanks for the feedback on the 4.88's. But you went from 6.2petrol to 6.7diesel after 45k; why?
Very glad to hear on the Maxxis Razr AT, keep me updated as you go along. Had you driven on any of the other tires on my list? I'm down to the Maxxis RAZR AT vs Yoko Geo X-AT.

So, the 4.88's...I put about 200mi on the truck today, driving all over town multiple times, ranging in speeds from 25-45mph. Lots of stopping, starting, slowing, accelerating. Then I'd pull over and let the drivetrain cool for a bit, then go again. Dogs probably got sick of seeing the same sights over and over.
I can't say I notice AS much of an increase in power on city streets as I was thinking I might get...but when I got into some throttle it seemed to go a bit better with less effort than before. Trans shift points seem different so I need to get used to that. I found myself manually tapping the +/- on the column shifter to stay in 4th gear max on city streets, else it'd get into 6th and kind of lug at low RPMS like it did before. I haven't driven the truck in 6+wks so perhaps I'm remembering differently (I drive too many different vehicles for work so they often gel into one).
Thankfully no annoying noises from the rear Nitro 4.88; maybe a low resonance murmur that wasn't there before, but I have to really strain to hear it. But there is a definite whine from the front, especially on decel, and especially going down an incline under decel. Must be a Yukon whine. <shrug> I'll think of it as a mini supercharger whine and not worry about it; not worth spending money to have a Nitro 4.88 put in the front instead. BUT, if I were to do gears again, I'd go Nitro front and rear. In fact, pro installer, who's been using Yukon forever, was so impressed with the Nitro fitment, that he said he's going to move to Nitro from now on.
I still need to get the Eaton E-locker wired up to an Aux switch.

Here are pics of the final pattern set.
Yukon rear;



Nitro rear (installer was really impressed);

 

[Skinhyfish]

You asked about going to a diesel.. I went to a cherry old 7.3. Do miss the gas for the CO winter starts. Around town your gears might not feel different but around here, I went from 3rd at 60mph up a hill to 5th/6th. The Offroad stop to go climbing over things was waaaayyy better. Be consistent on the break in and you will be happy!! Last offer is an5 star tune… it made the truck day and night

 

[mk216v]

You asked about going to a diesel.. I went to a cherry old 7.3. Do miss the gas for the CO winter starts. Around town your gears might not feel different but around here, I went from 3rd at 60mph up a hill to 5th/6th. The Offroad stop to go climbing over things was waaaayyy better. Be consistent on the break in and you will be happy!! Last offer is an5 star tune… it made the truck day and night

Say whaaat?! A 7.3L PSD with 4spd auto? You're going backwards LOL.
Will keep breaking the gears in properly. Good to hear on the 5Star tune, thx!