Deciding on towing upgrades.

[dcarver]

So i've been trying to decide what to throw my money in to for endancing my 03 suburban's towing performance. It has 120k 5.3 and 3.73 rear end LT 245/75/17s. I've been kicking around the idea of upgrading to 4.10s since a local shop can get me out the door for $750. But i'm unsure of the gains I'll see since I already have 3.73s. I also have been considering Shorty headers and cat back exhaust as well as a tune. Yes I said shorty headers. I've been finding on the interweb that shorties give you more low end torque (around 2500 rpm) which is where I need it. Any opinions if that isn't true? Anyway, I've been given a budget of 1k from the boss so let me know what y'all think is the best way to go for STRICTLY towing

 

[NathanJax]

How's the tranny? with 120k on it and a complete stock tranny, I would worry about heavy & continual towing with it.

 

[livingez_123]

My trailer is a tad under 10k, I have 3.73's now and don't have any issues. But if I were to tow my trailer around more often and on longer trips, I would change out to 4.10's in a heartbeat. I don't tow over 60 mph anyhow and I don't think there would be any MPG loss, if any a slight gain. My trans is not stock, I have a full Monster in a box kit in it and a larger cooler with its own fan. I haven't seen any temp issue.

 

[Gzes]

I would look into upgrading the trans. Then intake, tune and other various little things will make a big difference

 

[NathanJax]

I have a full Monster in a box kit in it and a larger cooler with its own fan. I haven't seen any temp issue.

Good idea... bigger cooler with fan is probably the 1st thing I'd do.

 

[dcarver]

The trans is stock but I keep and eye on the tranny temp and it never gets over 190 when towing up long grades. I've thought about investing in upgrading the internals but I'm very cautious with the speed I tow at and keeping OD off as well as fluid and filter changes about every 35k due to the towing. Tranny guy did state after the last pan drop that there were barely any metal shavings in the pan and it may have been rebuilt by the PO. I pull at 60-65 depending on terrain and wind so I'm not sure if changing to the 4.10s will get me that much more into the power band since I'm turning about 1800 rpms currently and IDK if being in at 2000rpms will make that big of a difference.

 

[ezdaar]

This should be your First priority.

This Trans cooler and the brackets from Performancetrucks.


Followed by vette and billet od servo's
Then Electric fans.

 

[MojaveDesertJK]

Regearing for the purpose of towing can be a good idea. The other upgrades mentioned can add lots of performance to your rig, but according to specs, stepping up in gears alone can often add 1000 pounds to your capacity. My 05 Yukon came with the tow package with the small tranny cooler and 3.73 gears and a max tow of 7700lb. It towed my 7000lb tt just fine along the hwy without a problem. The manual stated that 4.10 gears bring me to 8400lb. I regeared to 4.56 because I tow a lot in mountain ranges. My wife loves camping in the mountains. That little Yukon is a towing machine!

 

[Vgreid]

I have an '07 Yukon XL with the 4.10 and tow a trailer weighing in about 8,000lbs. I love the 4.10, really makes the most out of the 5.3. It does pretty well towing this around, granted our area is not that hilly. However, a quick drop to third, and I am turning 2700 rpm at 65 mph, and it does real well. I don't push it hard, letting speed rise and fall in the hills, but nonetheless, the 5.3 does a surprisingly respectable job with the 4.10. My previous Avy with the 3.73 towing a slightly smaller trailer seemed more sluggish to me, but its been a few years.

I think its not just where you will be in the power band that helps but that you also have a bit more torque multiplication going on with a lower geared diff, and that makes a difference as well. So, you get both benefits from a torque perspective.

Without a trailer, the 4.10 climbs hills like a mountain goat. This summer, we went from MI to FL, covering several mountain roads along the way, and the Yukon went the whole way without a downshift (it's a 4 speed), and got about 18.5 mpg, loaded with family and gear.

To your question, is it worth $750 ... well that's a tough one. Is it better for towing, absolutely. It is the best bang for your buck, well, I dunno. Personally, I would just drop it in 3rd and leave it there in tow/haul mode. You would probably be running 2,500 rpm at 65mph, rather than 1,800 in 4th, and you won't really see much a fuel economy difference while towing imo.

 

[scoobyxj]

Personally I'd go with the gears first off. If it was mine I'd go 4.56, and then play with tire size to get my final RPMs-MPH in the range I wanted. With doing the gears first you're lessening the torque needed through out 90% of the drivetrain. That all translates into lower stresses, and less heat in the trans. Heat is the #1 worst enemy of a trans. It hardens the internal seals, and causes slippage issues which then ruins clutches.