3.42

What will be the advantages and disadvantages going from 3.42 to 3.73? On Volvo D16 535hp with Eaton Ultrashift plus 18 speed, currently with 22.5’s running 76mph @ 1600rpm’s.

 

What kind of wagon you pulling and what’s your GVW? If you’re under 100k, stick with what you have. That 16 liter engine can change the rotation of earth even with 3.42s

 

3.73 would be better out of the hole. Make it easier to get heavy loads rolling and less strain on the driveline (especially on an uphill) vs a 3.42 ratio.

3.73 will increase the cruising RPM. May or may not have a noticeable impact on fuel economy. All depends on how much load you're putting on the engine.

 

I pull a dry van mostly around 30k, every now and then I pull a heavy load 40-44k. Definitely under 80k.

 

Leave it be. Your engine should be more than strong enough to do anything you need it to do with 3.42s.

 

The reason I was looking is truck is 2007. I just got the dtiveshfts splines and yokes replaced, balanced and all that. The rearends are pretty rusty, I mean real rust. The front diff has stated leaking quite a bit, the power divider has a pretty good size play (I think over a 1/4 inc) when I moved the yoke up and down. And the output on the back of front diff which connects the two drives also has a leak. I know it’s going to cost quite a bit to repair all of that, so, I was looking at cutoffs to replace them both DIY at home. I found fairly new a 2016 with 2.64 and a 2019 with 2.48 at an unbeatable price, wondering if one of these will work? If yes which one will work best?

Thanks a lot for your time! Very much appreciated!

 

Those 2.XX ratios will probably be pushing it.

 

I know this is a old thread .
I have a 2013 pete 388 with 550 hp ,1850 torque , 18 speed Eaton, 3.42 rears . It's a 70 " standup sleeper dbl framed back half of truck . 46k drives , holland fw35 5th wheel , AirTrac suspension . I have a Muncie dual line wet kit . I'm interested in pulling a 55 ton trail king hydraulic rgn. Do you think this set up will work or do I need to swap for 3:90 rears .

 

You can make it work, 550 hosses with 18 speed will give you plenty of options to keep it pulling. 3.90 would probably work better, but you can just keep it in a lower gear for off road.