Hi everyone,I'm new to this forum and have a question about my 2013 Sierra 2500 HD with a 6.0L and 3.73 gear ratio. It has a tow rating of 9400 lbs and in the manual it says if I had 4.10 it goes up to 13,000 lbs. I'm towing a 8,000# Coachmen Adrenaline 31 foot bumper pull. I just bought the trailer, and it pulls fine up to 60 mph or so, after that the RPMs stay close to 3000. I've only made two trips so far, one to purchase and one to an RV park this weekend. The truck drops a gear and gets to around 3500 rpms on steeper hills, on smaller hills it maintained speed with no gear change. I hate to hear the engine rev up to 3500, is that a lot of RPMs for the truck? My main question is, do you guys think I should spend the money to change the gears to 4.10? It's a 4x4 so I'd have twice the cost. I only tow on weekends and mostly nearby, but I have big plans to take family trips and venture a little farther. I drive about 1000 miles a month when not towing (work commute). Also, there was no issue at all with stopping, I can stop on a dime if needed. Any help would be appreciated. Thanks.....Jason

Let trans do its job, those vortec motors can rev high for long periods with no harm. Where you thinking about 500 for gears change ?? then worth the gamble.

I got a 6.0, 3.73 truck.... Put it in manual fifth, set tow haul, set cruise and let it rip...

Mine has the 4 speed but it pulls my 7400# Rockwood at 65mph in 4th and locks the converter up; 65 mph = 2100 rpm on mine weather in tow/haul or not. yours might be on the verge of shifting to next gear you have to find its sweet sport.. But 3-4000 rpms is not much for these engines they love to run but also love fuel..

I pulled a heavier TT (about 9K lbs GVW) with my 07 Chevy 2500 LTZ with the same setup. It's gotta rev to make its power...believe me it can handle it...as a prior poster said lock out 6th so it won't hunt when you're towing...if you change your gears, you'll probably nuke your warranty

Welcome to the forum Jason!!If the loaded to camp weight of your Coachmen is 8,000, you should have no problem towing.It will not hurt the 6.0 to run at 3000-3500. I am sure you will see an increase in fuel useage though. With the 6-speed tranny, 5th and 6th, should both be overdrive. It won't hurt to tow in 4th when necessary.I don't think you need to spend $1500-$2000 (guessing) to go to 4.10 gears, for your limited towing useage.Enjoy your new trailer,Jerry

2013 Sierra HD, is a gear change worth it? | Good Sam Community

26 Replies

jbufton
Explorer
Feb 25, 2014
Thanks for all the tips everyone. They are very helpful. I think I'm going to stick with the gears I have and get used to the way the truck operates. I was most worried about the RPMs but now I have a better understanding of how the truck is supposed to run. You guys are great thanks again.
intheburbs
Explorer
Feb 25, 2014
kaydeejay wrote:
jbufton wrote:
Thanks guys, now I understand that it will actually run higher RPMs with the lower gears. I think I'm going to stick with it for a bit and get used to the way the truck runs. The truck maintains speed no problem just gets a little throaty up steeper hills. At lower speeds there's no issue at all.
That engine will run 4000 rpms all day long. Peak rpm is north of 5500, so you're not even close!
You have a 6-speed transmission, so just lock it into the gear where it's happiest (probably 5th), select Tow/Haul and let the computer work its magic.
It won't let the engine lug or over-rev. In fact, it's probably smarter than you or I!

This is the best advice. I know it sounds counter-intuitive when talking about a V8, but this motor loves to rev. I just dragged my trailer through the mountains of Tennessee and Kentucky on a 2000-mile round trip. Never once did I feel the need for more power. The 6-speed is perfect for the 6.0.

On one particularly long, steep grade (probably 5-6%), I got parked behind a 35-MPH FedEx truck. Finally got an opening and nailed the throttle. I was up to 70 MPH by the top of the hill. I also stopped at the scales that day - 14,020 lbs rig weight. Save your money, don't worry about re-gearing.
Buck50HD
Explorer
Feb 24, 2014
The tow ratings need to cover nearly any condition, including launches on extreme grades. Just lock it out of 6th on the flats and let it spin on the hills. It will still run approximately the same RPM with lower gears because it still has to make the same HP (although the gears would be more closely spaced to allow finer RPM adjustments).

At 3500RPM and close to 380 ft-lb, it's making 250 HP which is approximately enough to keep a 16000 lb truck/RV rig at 60MPH on a 6% grade. You should only need around 100 HP to keep it at 60MPH on the flat so ~2200RPM(I think that's where you'd be in 5th) would be plenty with the 6.0 TQ curve. Running 6th gear, you'd be making just over 100HP so it is likely to hunt. That's where the diesels shine. Just a little boost, 800 ft-lb and you're over 200HP in a heartbeat.
Taco
Explorer
Feb 24, 2014
Very likely not worth it. Some times the 4.10 will run lower rpm and other times it will run higher. If it lets you hold a higher gear then you can run lower rpm. but if it still needs to downshift to the same gear it would be in with the 3.73 you will be even higher rpm. The truck makes it's power at higher rpm, no amount of gears can change this.

I personally have a very similar truck (2012 2500hd 6.0 3.73) I totally ignore the tow rating and just make sure to keep it under the axle ratings.
Redsky
Explorer
Feb 24, 2014
You would have been far better off to locate a 2013 truck with 4.10 gears. I never buy a truck or SUV for towing without a 4.10 rear end even if it makes the search take longer and negotiations with the dealer trickier.

Where the 4.10 helps is with acceleration and when going up a steep grade. The engine will be in its peak power band at towing speeds and provide more power.

Options are to change gears, change truck, change trailer, or live with it as it is. Hopefully you will do your research next time before you buy a new tow vehicle instead of after the fact.
LowRyter
Explorer
Feb 24, 2014
remember, if you go to 4.10 gears you'll be revving the motor higher in all the gears at the same highway speed. You're hoping that the it might not kick down to lower gears so often when towing- I am not sure how true that would be.

You appear to be well within your tow limits with 3.73 gears.
kw_00
Explorer
Feb 24, 2014
I have the 6.0 with 6 speed and 3.73 gears. I pull more weight then u without any concerns. I lock out 6th and run in 5th in Florida. Out of state I run 4th in the hills without complaints. Engine revving to 3500rpm is far... far.. from killing it. I have owned 6.0s for several years and love how this engine series performs.
bmanning
Explorer
Feb 24, 2014
I'd stick with the 3.73, as you have a "modern" 6-speed gearbox.

IF you ever go to a larger, heavier trailer you can always consider deeper gearing at that point.

If you had the older 4-speed, I'd have recommended the gear change. I went from 3.73 to 4.30 in my 2008 5.4L gas F250 (heavy truck, XLT crew cab 4x4) and it made a great deal of difference.

I think gearing swaps are very vehicle-specific, and my heavy truck with a small-block gas engine benefitted greatly. In other cases it's a waste of money.
APT
Explorer
Feb 24, 2014
retento wrote:
I got a 6.0, 3.73 truck.... Put it in manual fifth, set tow haul, set cruise and let it rip...

+1.

Don't let it try to shift into 6th gear. This can slow down enough that it downshifts to 4th gear and 3000rpm to bring your vehicle speed back up to what you want. 5th gear, 2200rpm at 65mph should be fine. Hills in 4th gear at 3000rpm, fine. Hills in 3rd gear at 4000rpm, fine. This engine wakes up over 3500rpm and pulls hard to almost 6000rpm. Peak torque is around 4200rp. Let it spin!
dodge_guy
Explorer II
Feb 24, 2014
I am still wayne_tw wrote:
jbufton wrote:
Thanks for the tips everyone! Yea I was thinking around $1000-$2000 for the gear change. I'm going to try manual 5th and tow / haul. The truck has no issues keeping speed just hated to hear the engine rev, but sounds like it will be ok.

Changing the differential gearing is no different that lowering a gear in the transmission. All the lower gearing of the differential does is cause the engine to rev higher. Manually lowering the final drive gear in the transmission (say from 6th to 5th) causes the engine to rev higher. Same same.

This goes around all the time. Changing the gear ratio is completely different than just dropping a gear. It in effect changes all the ratios in the trans, that is why a truck with 4.10's will tow more than one with 3.73's! With my X and the 3.73's the rpm's were too low in 3rd at 65mph, it would lug a bit to much, and too low in rpm to make O/D usable when towing. With the 4.30's it brought the rpm up about 300 rpm in each gear when towing just enough to make each gear in the transmission more efficient.

And like was said unless you know it will allow you to run in O/D changing to the 4.10's will raise the rpm in all gears, however even a few hundred rpm can make a big difference!