2014 Silverado 3.42 or 3.73

[soren]

Hopefully some of you have a bit of experience with the newest GM trucks? As a bit of background. I have towed a considerable amount in the last 15 years, with roughly 1/2 dozen TTs and almost as many 1/2 and 3/4 T GM trucks. The issue here is that I'm buying a new 30' TT. The dry weight is 5600LBS, gross of 7500lbs. I would really prefer a GM 1500 Crew 4x4 to pull it with. My last trailer was about 1000lbs lighter and did well with a 5.3/3.73 older Tahoe.

Now that we are in a world of much higher power from the same 5.3 and things like 6 speed transmissions, I'm not sure what I really need? The issue is that trucks on the lot are typically rate at 9500lbs. with the 5.3/3.43 combo, and every dealer has a pile of them. The upgrade is the Max tow package with the 3.73 and roughly an additional ton of rating. The package is overpriced for what you get, and it's pretty rare. Bottom line is, what can I expect when pulling 7K or so, with the 3.43?

[soren]

Wow, The dealer was actually a bit over 300 miles away. Fourteen hours, 600 miles and doing the deal in the middle of all that, loooong day. Not to mention the dealer was in Buffalo, NY. which is colder than a witch's ....... elbow. After a fifteen year run of nothing but various GM trucks for my business and personal use, all I can say is that I'm impressed. The wife made the same comment several times, "It's hard to believe that this thing is a pick-up" Nicest ride, and features of anything I ever owned, or driven, that could haul a load of manure.

As for the new TT, we found a screaming deal on a leftover 30' Jayco Eagle, which is a pretty heavy lump to drag. It's 6820 empty, with an 8800lb gvw. That swayed me toward hunting down the Max. tow option, since it was getting a bit too close for me, with the 3.42 set-up. If your first thought was, "this guy needed a 3/4 ton" you may be right, but it wasn't a viable option. the wife is pretty disabled, and simply couldn't get UP and into any of the 4x4 2500s from any of the big three.

Thanks for listening, and if you're anywhere north of the equator this winter, try to stay warm 🙂

[APT]

Cool, thanks for the update! Drive safe and let us know how you like your new toy, I mean truck!

[soren]

ExxWhy wrote:
I think the most important thing you need to find is the max payload package. Doubt power will be that much of an issue with either gear ratio.

After searching for a few weeks now, we are leaving shortly to drive 260 miles to pick up a new truck. Unfortunately the options are extremely limited with regard to how the latest ones are built. There are no payload options, and the only way to get a 3.73 is with a max. tow package, which sets the vehicle up pretty well with a new rear(not just a gear change) bigger springs, more cooling, etc.... The max tow pac. is extremely rare, and two dealers looked into it for me and claimed that it didn't even exist, LOL. Another told me that tow mirrors are no longer available. Since I found a unit with both, it's worth the drive.

Thanks for all the help, everybody.

[ExxWhy]

I think the most important thing you need to find is the max payload package. Doubt power will be that much of an issue with either gear ratio.

[fly-boy]

Just bought one with the 3.73 for pulling a couple smaller trailers we have. No way I would be happy with the 3.42- period.

I think you need to balance what the truck is really for. If it is primarily for towing/camping- bite the bullet and get the 3.73. If it is mostly a daily driver and just an occasional tow vehicle- get the 3.42 and just live with it.

[goducks10]

Beltzy wrote:
I just traded in my 2012 1500 silverado 6.2L 3.42 rear end and i was pulling my 31 ft 7200 dry weight toy hauler with that. The 6.2 with the 3.42 was very impressive and tons of towing power out here in the Utah hills. Like any gasser though i would average 8-10 mpg pulling depending on the road. The reason i upgraded was I had 2 close calls on stopping this past year and did not feel comfortable with how the 1/2 ton frame/brakes handled it. I was one of "them guys" that bought the truck first then the trailer.

Nothing like a good exhaust brake.

[Beltzy]

I just traded in my 2012 1500 silverado 6.2L 3.42 rear end and i was pulling my 31 ft 7200 dry weight toy hauler with that. The 6.2 with the 3.42 was very impressive and tons of towing power out here in the Utah hills. Like any gasser though i would average 8-10 mpg pulling depending on the road. The reason i upgraded was I had 2 close calls on stopping this past year and did not feel comfortable with how the 1/2 ton frame/brakes handled it. I was one of "them guys" that bought the truck first then the trailer.

[Empty_Nest__Soo]

My current truck has the 5.3/3.42 combination. Last truck was a 1998 GMC 2500HD with 6.0/3.73 combo.

Before buying the new truck, I did a lot of research and number-crunching. I was skeptical of the 3.42.

It turns out that the net output thru the 6-speed tranny is lower gearing when compared to the HD 5-speed manual tranny in my last truck. That truck had the 3.73 differential.

Combine the lower gearing thru the tranny with the higher geared differential and the net gearing for the whole system, from crankshaft output to rear wheels, was about the same. Plus, the new 5.3 has a lot more HP and torque than the 6.0 in my old truck.

Old truck was rated to tow 6500 pounds, new truck rated to tow 10,000. (In the real world, the limiting factor on the new truck seems to be hitch weight/carrying capacity, not tow capacity.)

Wayne

[rider997]

soren wrote:
Hopefully some of you have a bit of experience with the newest GM trucks? As a bit of background. I have towed a considerable amount in the last 15 years, with roughly 1/2 dozen TTs and almost as many 1/2 and 3/4 T GM trucks. The issue here is that I'm buying a new 30' TT. The dry weight is 5600LBS, gross of 7500lbs. I would really prefer a GM 1500 Crew 4x4 to pull it with. My last trailer was about 1000lbs lighter and did well with a 5.3/3.73 older Tahoe.

Now that we are in a world of much higher power from the same 5.3 and things like 6 speed transmissions, I'm not sure what I really need? The issue is that trucks on the lot are typically rate at 9500lbs. with the 5.3/3.43 combo, and every dealer has a pile of them. The upgrade is the Max tow package with the 3.73 and roughly an additional ton of rating. The package is overpriced for what you get, and it's pretty rare. Bottom line is, what can I expect when pulling 7K or so, with the 3.43?

I have the same truck (2014 5.3L/3.43/crew cab/4x4) and it pulls a 6,000 lb trailer with no issues, up to around 7,000 feet of elevation or so (at which the truck is losing around 20% of its rated horsepower).

I would say that if you're sticking with the 1/2 ton (1500), the 3.73 gears are definitely more peppy, but the 3.42 is not a deal breaker.

The 2014 5.3L has more HP and torque than the Vortec 6.0 in the 3/4 ton trucks, and the truck's GVWR is lower, so it has no problem pulling the load. The truck will accelerate and hold a grade with no problem. The 6 speed tranny mapping is very good and does not hunt on up-grades. The grade braking function (the transmission will hold a low gear on down grades to allow engine braking and minimal to no use of the brakes) also works like a charm.

I get 10-12mpg pulling a travel trailer at 55-60mph (this includes hilly/mountainous terrain and lots of wind); around 16-18mpg pulling 6,000 lbs of payload on a utility trailer (negligible wind resistance), and about 21mpg unloaded highway mpg.

The new trucks have pretty decent payload ratings - about 1900 lbs even with the crew cab 4x4, so tongue weight and bed payload probably won't push you to a 3/4 ton unless you're carrying motorcycles or the like the bed of the truck.

[Need-A-Vacation]

Soren,

As others have mentioned, I have pulled 7k with our previous tv, 2010 Silverado 1500 CCSB 5.3/6spd/3.42 combo. Never felt I NEEDED more power when traveling "Up North" here in MI.

Main reason we now have a 2500HD is we were out of payload!!! Watch that and you should be fine!

[fireman41]

The company I used to drive for had semi trucks that had 2.94s tide to an 10 speed direct drive transmission. They pulled ever dit as good as the the trucks that had 3:55 and 10 speeds with over drive

[mkirsch]

The idea that you need 3.73, 4.10 or an even lower gear ratio is outdated 1970's thinking, from back when a big block V8 had a whopping 175HP and transmissions had 3 gears.

Gearing is gearing. Doesn't matter if it's in the transmission or in the rear end.

Nowadays it's in the transmission. The Chevy 6-speed has a super-low 1st gear to get the load moving. 4.something:1 vs the 2.something:1 in a 4-speed.

The Chevy 6-speed has two extra gears between 1st and "direct" to accelerate the load. In fact, the Chevy 6-speed does not have a "direct" (1:1 ratio) gear in the transmission at all. It has a 1.15:1 4th gear and a .9:1 (IIRC) 5th gear.

The fact of the matter is, the engine with a 6-speed/3.42 combination will be turning RPMs similar to a 4-speed/4.10 combination.

[BenK]

What really matters is the effective ratio at the pavement vs the ICE's torque
curve. Toss in HP curve if you wish, as most understand HP better than torque

[roadrider10]

Same experience here also. We are towing 6300 lbs. with a 2012 Sierra CC and 5.3 /3.42 axle. Plenty of power on hills. We tow long distances and get a low of 9.5 mpg. to a high of about 11.5 mpg. Depending on terrain, wind etc.
The new 5.3 should be better with increased payload, power and torque.