Hi all, I have a 2013 GMC Sierra with a 5.3 litre engine and 3.73 ratio rear axle. It has about 76k miles. It has a max tow rating of 9500 lbs. I'm looking at buying a 2018 Siverado under 30k miles with a 5.3 litre engine but 4.34 ratio rear axle and a rated towing capacity of 300 lbs less at 9200 lbs. The 2018 has a few nice bells and whistles that I'd like to treat myself to. Question is will there be a noticeable difference in the newer trucks ability to tow? Will it seem like it is under powered in comparison? My trailer has a dry weight of 5625 lbs and GVWR of 6995 lbs . My current truck does bog down somewhat on the steeps and I really wouldn't be happy if there was a noticeable difference with the new truck pulling the big hills. Advice appreciated. Thanks for reading.

You want to look at the HP difference. I believe the 2018 has a handful of more HP. A few more gears will keep it in the torque band a little better also.The newer truck will pull marginally better than your old one IMHO. Not night and day; just marginally if I'm correct about the HP.

wtmtnhiker wrote:Hi all, I have a 2013 GMC Sierra with a 5.3 litre engine and 3.73 ratio rear axle. It has about 76k miles. It has a max tow rating of 9500 lbs. I'm looking at buying a 2018 Siverado under 30k miles with a 5.3 litre engine but 4.34 ratio rear axle and a rated towing capacity of 300 lbs less at 9200 lbs. The 2018 has a few nice bells and whistles that I'd like to treat myself to.Did the previous owner re-gear with a custom ratio? Do you know if they also performed other modifications? That would worry me buying something used that's been heavily modified.

4.34 gear ratio has to be a typo. What ratio does it really have? If it's numerically lower than a 3.73 then I would say yes, you will notice a difference towing. It will feel less powerful, not accelerate as well, and be harder to keep the speed under control going downhill. If it is numerically higher than 3.73 it will also be noticeable better in all the aforementioned areas.

“The newer truck will pull marginally better than your old one IMHO”I agree with Turtle. My 2020 Silverado is better than my 2015 Tahoe but not by leaps and bounds.

KD4UPL wrote:4.34 gear ratio has to be a typo. What ratio does it really have? If it's numerically lower than a 3.73 then I would say yes, you will notice a difference towing. It will feel less powerful, not accelerate as well, and be harder to keep the speed under control going downhill. If it is numerically higher than 3.73 it will also be noticeable better in all the aforementioned areas. Tight, sorry. 3:42

Tow Vehicle question | Good Sam Community

Turtle_n_Peeps
Explorer
May 30, 2020
You want to look at the HP difference. I believe the 2018 has a handful of more HP. A few more gears will keep it in the torque band a little better also.

The newer truck will pull marginally better than your old one IMHO. Not night and day; just marginally if I'm correct about the HP.
GordonThree
Explorer
May 30, 2020
wtmtnhiker wrote:
Hi all,
I have a 2013 GMC Sierra with a 5.3 litre engine and 3.73 ratio rear axle. It has about 76k miles. It has a max tow rating of 9500 lbs. I'm looking at buying a 2018 Siverado under 30k miles with a 5.3 litre engine but 4.34 ratio rear axle and a rated towing capacity of 300 lbs less at 9200 lbs. The 2018 has a few nice bells and whistles that I'd like to treat myself to.

Did the previous owner re-gear with a custom ratio? Do you know if they also performed other modifications? That would worry me buying something used that's been heavily modified.
KD4UPL
Explorer
May 30, 2020
4.34 gear ratio has to be a typo. What ratio does it really have?
If it's numerically lower than a 3.73 then I would say yes, you will notice a difference towing. It will feel less powerful, not accelerate as well, and be harder to keep the speed under control going downhill. If it is numerically higher than 3.73 it will also be noticeable better in all the aforementioned areas.
Lwiddis
Explorer II
May 30, 2020
“The newer truck will pull marginally better than your old one IMHO”

I agree with Turtle. My 2020 Silverado is better than my 2015 Tahoe but not by leaps and bounds.
wtmtnhiker
Explorer
May 31, 2020
KD4UPL wrote:
4.34 gear ratio has to be a typo. What ratio does it really have?
If it's numerically lower than a 3.73 then I would say yes, you will notice a difference towing. It will feel less powerful, not accelerate as well, and be harder to keep the speed under control going downhill. If it is numerically higher than 3.73 it will also be noticeable better in all the aforementioned areas.

Tight, sorry. 3:42
rjstractor
Nomad
May 31, 2020
The newer truck has another 40 hp but with the taller axle ratio it will probably pull about the same. IIRC the 2013 and 2018 use the same 6 speed transmission.
bikendan
Explorer
May 31, 2020
compare payload capacities between the two trucks. get the one with the higher payload capacity.
APT
Explorer
May 31, 2020
Are you sure your 2013 has 3.73? I thought you could only get 3.42 with the 5.3L and 6-spd?

2014+ GM half tons have slightly more HP. I expect it will feel about the same when towing.
wtmtnhiker
Explorer
May 31, 2020
APT wrote:
Are you sure your 2013 has 3.73? I thought you could only get 3.42 with the 5.3L and 6-spd?

2014+ GM half tons have slightly more HP. I expect it will feel about the same when towing.

I was told by the dealer that it was 3.73. I'm tending to doubt that now.
Grit_dog
Navigator
May 31, 2020
It'll tow marginally better, but not enough to be the reason to upgrade trucks.
2016 Silvy 5.3, 3.42 currently. Have had 2014, 2011 and 2008 for comparison. All 5.3 half tons with tow pkg.

Have towed the most with the '16, have had it the longest. It'll keep 10-14klbs of flatbed trailer moving at the speed limit up 4-5% grades at lowish altitude, but that's it's limit for towing power. And it's wound to the beans with anything over about 8k. Haven't towed any high profile trailers bigger than my 32' enclosed V nose snomachine trailer at about 6klbs. Basically a really lightweight long TT.
It feels like a 12k flatbed on the same hill at 60mph.