This is a great thread.
I got a 4.10 in my 22 6.4 Laramie 8sp about 7 months ago (10/2021); that was when the inventory issues were beginning to really tighten. I would’ve probably gotten a 3.73 but couldn’t find one in that environment.
NOTE: This was my first three-quarter ton truck so take my opinion for what it’s worth.
I had a POS 5.3L GMC 1500 AT4 in the shop 4 times with 15,000 miles and I had to get out of it so I did not have time to wait for inventory to improve. I felt like I was lucky to find the truck I wanted at MSRP while others were gouging at $4000 over MSRP. Approx $61K @ Lou Fusz St. Louis - great experience.
Still not 110% convinced which is the right axle, but I’ve got nearly 20,000 on this one and I love it. I wonder what a 3.73 would be like but I’m content with my 4.10.
Allow me to offer some opinion for those who may still be debating:
The extent to which I may be overpaying (if any) in hwy gas is likely very negligible and something that resale alone may earn back because this is a legitimate, occasional heavy hauler and plenty capable of the larger tires - two significant positives in the 2500 community. If you are towing heavy w/ any frequency or put on anything other than a stock tire on a 3.73, there is a potentially steeper slope of error (cost/regret) IMO. If you are doing both I think a 3.73 would be notably undesirable.
As mentioned before if you’re not above 12,000 pounds more than once or twice a month a CTD is worth nowhere near the up charge and maintence expense. Occasional over 15K is where for the 4.10 stays compelling. That is quite a bit of weight and more than a lot of people in 3/4ton trucks will ever hook on to. The 3.73 gets more debatable in these 2 scenarios. Even if i’m not using it like that the next owner might…
On stock tires (285/60r20) I get the following:
12.5-13.5 mixed
17 hwy
19 coming home from Colorado slow rolling at 65-66, but took it a while to get there.
NOTE: I had a 2014 F150 FX4 that could not get the same MPG. This is twice the truck of that Ford.
I really don’t tow heavy. I have an 18 foot utility that very rarely hauls near capacity.
I have a single axle utility that’s used very frequently. Fully loaded (5K gross) the MPG numbers really don’t move enough to notice vs empty. That’s not really a heavy trailer but I have it all the time w nick nack stuff. That same trailer would knock my prior half tons down to 12 - even a 2018 F150 XLT W 4.10s on 34s.
I just ordered some 295/65r20 (35s) to put on it. If you do the conversion on tiresize DOT com it still will have a stronger axle than a stock 3.73. It’s closer to 3.91 w/ 35s. 35s on a 3.73 knock effect ratio down near 3.55 - NOT a ratio I would want on a truck this heavy and especially not w/ any kind of load.
If you’re putting on a taller (or heavier) tire on, 4.10 is the way to go IMO and after what I have experienced in the first 20,000 miles.
From my experience:
1. I do think the stronger axle helps you in the city without question. I was somewhat surprised at how much heavier these trucks are. Handles noticeably different than a half ton, and that’s without the thousand pounds of extra weight a CTD creates.
The comment was made earlier but it’s a lot more weight to get moving off the line.
2. 4.10 helps you if you get a bigger tire without question - especially regarding #1.
It gives you better performance and is still manageable if you go easy on the highway.
If you are predominantly hwy and stock, a 3.73 will be what 2mpg better? If you’re driving close to 80mph the 3.73 is better. But, if that is the case why the hell are you in a three-quarter tow pig???
What does 2 mpg equate to per year $1K? What is that $5000 over the life of a vehicle? You’ll spend that on the 1500 getting it to look as good as a 2500 and your suspension won’t last nearly as long…
If you’re deadheading all the time, consider getting a 1500 with 3.92 axle on 34s. But even then you have a truck with a nose that looks like a doorstop.
One of the coolest things about a 2500 (for me) is the blunt nose. Yes you pay for it in wind resistance, but it looks like a truck vs. a truck that’s being designed to drive like a car … (1500s)
I can say that although I was originally leaning toward 373 I’m actually glad I ended up with a 4.10 but for reasons I’ve only discovered since having bought it.
I will say that when the transmission is down shifting you can sometimes feel it going down into the low gear. It almost feels like it’s binding up, but it’s simply downshifting - to an extremely low gear. It first concerned me, then it annoyed me, now I just ignore it because it’s not overly frequent or overly noticeable. A 3.73 would prob not do that.
I would vote for a 4.10 unless your empty and hwy 75%+ of the time.
$.02