A 5.29 puts you at 3000rpm at 80mph. that engine will spin 3k for 10s of thousands or miles (if all other factors are good of course) but even if that wasnt true lets be realistic here....how many miles are you REALLY going at 80mph? Few hundred a year tops? cant be that many if you are staying off the freeways. youll still have a theoretical top speed of 160mph so why gear any higher? a tall gear just makes a truck feel sluggish off the line and out of corners. short gears are fun!
How much running around nevada have you done? Silverstate 300 course, Vegas 2 Reno course... ENDLESS 80mph runs!!! ENDLESS!!!! I'm not talking Barstow. I've got runs where I'll do 100 miles total out of a 250-300 mile trip at those speeds.
One of my favorite runs is to start in Boulder City and run to Laughlin in the dirt.
(the point of those videos isn't to show speeds, it's to show the types of roads... In the 2nd one, that opening road goes all the way to the horizon like that for instance.)
I just hopped on mapping software and VERY quickly roughed out the mileage of what the wide open sections on that alone are.... Roughly 78 miles of that run would be 80+mph with the shortest of those high speed run sections being 9 miles long, literally wide open with only a handful of check ups. One stretch is 15+ miles long where I would easily be running 80+ MPH. These aren't beat to crap roads, they're wide open rally type roads with sweeping turns and rollers that make for really fun air time at high speeds.
Or how about the Valley north of Beatty, that the V2R course runs. Fun stretch!!! I just mapped it roughly... That stretch is 22 miles long. Last time I ran it in our race truck I lifted off the gas twice for 2 silt pockets. Stock 3.4L V6 on 35's with 6.0s would only push 80mph up those roads, I could've fallen asleep at the wheel wishing our truck had WAY more power cause 100mph across that valley for 20 miles is easily doable!!! That's only 1 valley... There's a few of them you cross on a run from Beatty to Tonopah. The 6 mile down hill run into where Pit 3 is usually setup, with exception of the one gotchya about 3/4s of the way down it, you never lift once and it's a 7 mile stretch.
BTW, and when I mean I would trailer my truck to the dirt... My version of trailer is I load up and trailer it to Boulder City, I unload it, do the run to Laughlin, stay the night, back the next day.
I trailer the truck to Beatty, unload it, run it to Tonopah, stay the night, run it back the next day. I'm not talking about doing runs from Blow Sands to Shell Reef and back. I'm talking 200-300 mile runs.
Again, I CURRENTLY run 6.0's and am ALWAYS looking for 5th gear. I'm talking ALWAYS!!! On a run I do from Jean to Pioneer Saloon and back... There's 40+ miles worth of lakebed, powerline road and frontage road on that 80 mile total run. Last time I did it I was running 90mph thinking why am I not doing 110 right now!!! Common lets go!!!
Let's talk Johnson Valley... That area can be as smooth or rough as you want it to be depending what trails you run. I make a point to stay off the race courses out there, that stuff to me is just rough and not even fun. I tell my race partner all the time, my goal with my truck is to be able to run our race speeds but feel like it's a casual cruise in my truck.
Again, like I said, currently with a stock motor and 6.0's I'm ALWAYS looking for 5th gear cause I'm ALWAYS screaming it in overdrive on the runs I do. And I'm talking 15-20 minutes straight which is where I'd love to be at 3000 rpm. My transmission does shift by the way... If I need more power I can shift down a gear to get out of corner. Do you really think anything about 35's with 500+ hp is going to result in the words "sluggish" out of corners when it's in 2nd gear?
I think based on partybarge I'm probably going to try a 4.86 or whatever it was he mentioned strength wise. Seat of the pants is there really much between like that and a 5.20ish something? I've never really messed with gearing changes other than drastic jumps on a vehicle. My exploder was 4.88's on 35's but the race truck is 6.0's on 35s vs my F150 that's 6.0s on 35's. All VERY different platforms though so I just don't know seat of the pants how much of a difference some of these changes make? I just know that i hate the 6.0's for how I use my truck and my gut feeling is something down around 5.0 is going to be much better but I don't want to go too far the opposite way either you know?
I know what you mean by long trips. I just did a 600 mile trip in my truck 2 weeks ago. Way different platform but I have 5.29s and ran 200 miles on the highway at 70-80mph. Other than a driveshaft vibration it’s perfectly fine.
On the other hand another truck in our group has 5.83s with no OD. He’s around 4K rpm at 70 which is pretty crazy for an hour+ straight on the highway but it’s been doing it for years lol
I've always been a low RPM driver... Only exception being the race truck cause, well it's race truck and it's toyota... LOL Even my daily driver which is a 300ish hp '67 mustang, I RARELY touch 4K rpm on it let alone 5K eventhough it'll sit there all day without issue. It's just what I prefer. I honestly don't know where my RPM's are at at 90mph in the truck, I just know everytime I'm sitting at 90mph I'm cringing wishing I had another gear.
I don't think lack of power will be an issue... My concern is that as much as I hate the 6.0's, I'm concerned to end up in the opposite side of the spectrum, make a change and realize crap! I still hate it but now I'm at the other end of the spectrum.
Who's got a 3rd member loaner program in place where I can rent a couple 3rds with various ratios to go testing with??? LOL
I was just thinking you should do this. Not sure how many people would jump on board though. Ive got a 31 spline with a detroit and 4.56 gears waiting to go in my rear end. though it looks like thats definitely lower than you want to go.
I'm also 35 spline... If I was ultra rich, I'd have my guy just go out with me and install each while I kick back and then when done I'd let him know which I wanted to run. But reality is I haven't figured out that uber rich part yet and I'm trying to only do this one more time and maybe get it right. First time around some well respected racer names advised the 6.0's I have now and well... Not thrilled with them as you can tell.