Max Tow vs. Z71 off Road ??

wrc7732 · August 4, 2015

So I just picked up a 2015 Sierra 4x4 with the z71 "off road" suspension.

It's a crew cab with the standard 6'6" bed (damn near impossible to find around here). I wanted the Max Tow package but it was the only one in the area with the cab/bed configuration i wanted that I could find after several months of looking.

Anyway, what does the Max Tow package consist of anyway? I know it has 3.73 gears instead of my 3.42, but beyond that I haven't been able to find much about it.

I looked in the manual and I see that in my configuration I can tow up to 9,100 lbs. Yet the max tow can tow up to 10,800 lbs. I know it sounds nuts, but there are times when I could really use that extra 1,700 lbs of towing capacity, and I'm wondering what I can do to get me there. Surely it's not all in the gearing?

Is the kit or something like it available in the aftermarket? Auxiliary coolers, front and rear gearsets, shocks, springs, etc.?

Thoughts?

Thanks,

Will

Sent from my iPhone using Tapatalk

Chris · August 4, 2015

Larger rear axle, 3.73, shocks, and possibly the integrated trailer brake controller. Not sure if that and the mirrors are still optional

wrc7732 · August 4, 2015

Larger rear axle, 3.73, shocks, and possibly the integrated trailer brake controller. Not sure if that and the mirrors are still optional

What do you mean by larger rear axle? As in a physically larger housing? Or just a more robust gearset within the same housing?

What about the leaf springs?

I have a brake controller, and the tow mirrors. (Added these last week)

Can't believe there's not a kit available that would get me where I need.

Sent from my iPhone using Tapatalk

Badass69 · August 4, 2015

Same housing. Ring gear goes to 9.75" from 9.5". Beyond that it would be coolers and likely a higher rating on the receiver hitch. And yes the brake controller

Sent from my SM-G900W8 using Tapatalk

wrc7732 · August 5, 2015

So hit h receiver is class IV, good for 10k lbs, or 12k lbs with weight distributing hitch (either way exceeding my current capacity). So okay there.

Coolers could be added I suppose.

Still wondering what suspension differences there are to help carry the extra load. Sounds like different shocks. What about leaf springs?

Sent from my iPhone using Tapatalk

Big Whiskey · August 8, 2015

The max tow package has upgraded rear springs that increase the payload by about 400 lbs.

wrc7732 · August 8, 2015

The max tow package has upgraded rear springs that increase the payload by about 400 lbs.

Thanks.

Where do I find me a set of those?? Not having much luck on eBay. Think the dealer would know??

Sent from my iPhone using Tapatalk

wrc7732 · August 14, 2015

Bump.

Any chance someone can list me the part numbers for the rear leaf springs for a 2015 Sierra Crew Cab, Standard (6.5') bed, that would come with the Max Tow package? I've got to get some stiffer springs out back. But I'm not looking for any lift.

Sent from my iPhone using Tapatalk

newdude · August 14, 2015

Axle assembly has a different part # for 5.3/3.73 gear and L86 than the 5.3 with 3.42 or 3.08. So, one could assume that the max tow possibly has a structural upgrade of some sort over the regular trucks. So...assuming not the worst scenario...$630 for rear gear set and associated gaskets, $1010 for front gear set and associated gaskets, $520 for springs, u bolts and u bolt nuts, and $200 for rear shocks. $2360 just in parts and then add what, maybe $1000 for labor? Installing the gears, shocks, springs and then having the truck reprogrammed.

If you really wanted an NHT, then you shouldn't have settled. Trade it and cut your losses.

wrc7732 · August 15, 2015

Axle assembly has a different part # for 5.3/3.73 gear and L86 than the 5.3 with 3.42 or 3.08. So, one could assume that the max tow possibly has a structural upgrade of some sort over the regular trucks. So...assuming not the worst scenario...$630 for rear gear set and associated gaskets, $1010 for front gear set and associated gaskets, $520 for springs, u bolts and u bolt nuts, and $200 for rear shocks. $2360 just in parts and then add what, maybe $1000 for labor? Installing the gears, shocks, springs and then having the truck reprogrammed.

If you really wanted an NHT, then you shouldn't have settled. Trade it and cut your losses.

I'm assuming from your post that you have access to part #'s and such.

Is there anyway you can confirm that there are actual structural differences between the axle housings?

Assuming that the GAWR would remain in range, my plan is currently just to replace the rear leaf springs and perhaps the shocks. So by the look of your list, I'd be looking at $720. I'd install myself, no issues there, and then maybe get an alignment if needed.

Can you tell me what the part numbers are for the springs and shocks that accompany the max tow package? Are the fronts the same, or are they different too?

If the axle can support the added load, the power is sufficient for my towing. I don't feel it's necessary at the time to go down the gearset change out, unless there's some other reason to do so beyond acceleration performance.

Sent from my iPhone using Tapatalk

newdude · August 15, 2015

23144506 spring, 11569811 u-bolt, 23156091 shock.

elcamino · August 15, 2015

rpo NHT

Max Trailering Package, includes 9.76" rear axle, (GT4) 3.73 rear axle ratio, with (MYC) 6-speed automatic transmission, (JL1) trailer brake controller, enhanced cooling radiator, revised shock tuning for increased control, heavier duty rear springs and increased RGAWR.

1 (SLE) - Includes (G80) heavy-duty automatic locking rear differential on 2WD models (already standard on 4WD models) and Z82 Trailering Package. Requires (L83) 5.3L EcoTec3 V8 engine and (DPN) power camper mirrors. Not available with (Z71) Off-Road Suspension Package. Includes (UHN) 18" X 8.5" bright-machined aluminum wheels. Requires (RBX/RBW) 18" tires or may upgrade to (RD3) 20" ultra bright machined aluminum wheels with either (RC7) on 4WD models or (QSS) 20" tires on both 2WD or 4WD models.

2 (SLT) - Requires (RBX/RBW) 18" tires or may upgrade to (RD5) 20" polished aluminum wheels with either (RC7) or (QSS) 20" tires. With (L86) 6.2L engine, requires (RD5) 20" polished aluminum wheels with (QSS) 20" tires. Requires (DQS) power adjustable, power folding camper mirrors. Not available with (Z71) Off-Road Suspension Package.

wrc7732 · August 16, 2015

23144506 spring, 11569811 u-bolt, 23156091 shock.

Thank you for the info. Huge help. This helped me investigate further, and it appears as though part #'s for both the axle housing and the bearings are the same regardless of whether you're running the 9.5" or 9.75" ring gear. Good news, I think. From what I understand my Z71 package adds some form of upgraded diff anyway, so can't imagine I'll tear it up with a bit of towing here and there. Far more likely I'll do that tearing ass around town.

I have another question if you don't mind.

Do I need 2 or 4 of part number 11569811 ?? The picture in the parts catalog has a line drawn to 2 of them, so it's difficult to tell.

Thanks again for all your help.

Will

Sent from my iPhone using Tapatalk

newdude · August 17, 2015

Thank you for the info. Huge help. This helped me investigate further, and it appears as though part #'s for both the axle housing and the bearings are the same regardless of whether you're running the 9.5" or 9.75" ring gear. Good news, I think. From what I understand my Z71 package adds some form of upgraded diff anyway, so can't imagine I'll tear it up with a bit of towing here and there. Far more likely I'll do that tearing ass around town.

I have another question if you don't mind.

Do I need 2 or 4 of part number 11569811 ?? The picture in the parts catalog has a line drawn to 2 of them, so it's difficult to tell.

Thanks again for all your help.

Will

Sent from my iPhone using Tapatalk

4 u-bolts total 2 per side.

BlackZ71Silverado · August 18, 2015

So hit h receiver is class IV, good for 10k lbs, or 12k lbs with weight distributing hitch (either way exceeding my current capacity). So okay there.

Coolers could be added I suppose.

Still wondering what suspension differences there are to help carry the extra load. Sounds like different shocks. What about leaf springs?

Sent from my iPhone using Tapatalk

The leaf packs on the max towing suspension are heavier duty. They are stiffer springs to accommodate for more weight. Count the leafs in the pack on your truck then count the leafs on a max tow. I am not positive but there may be an extra spring on those also.

Sent from my crappy iPhone 6

using Tapatalk