codes? capacities? confusion!
September 24th, 2018, 9:08 PM
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codes? capacities? confusion!
Hello Good Folks
New to towing and trucks in general, not new to logic and numbers. I have found and been even handed some incongruent information about the towing capacity derived from the options on my 2010 Suburban.
Here is what i got, sorry if its a novel but theres a lot i would like to clear up. I'll number my questions so you can pick and chose your replies if your kind enough to share your knowledge.
I purchased private 2010 suburban lt through a dealer at 124k km (so the private seller gets tax off his new car i assume?) it seems to be in great interior/exterior/mechanical shape so far.
Intent: This is to be the wife's infrequently used daily drive while on mat-leave, and the tow vehicle for 3 or 4 camping trips every summer from here on out, estimated driving distance ~500km each way. trailer not yet purchased, weight estimated at ~5-6k lbs (dont need to put water in it until at campground). Family weight + gear in car ~600lbs
I would like to install the most effective options to get the tow capacity to its highest engineered standard, not so I can tow anything pushing those limits but to create as large a gap as possible and increase the stability and safety those few times i will be towing.
So the dealer looked up the build sheet, ran the codes though some program which compared it to a 2012 yukon and told me that while it has the tow package, the towing capacity is 4600lbs (which is coincidentally the RGAWR)
1)The lowest rating is 5000lbs in the manual, why would he have a different number in the computer?
2)Are RPO code completely reliable and unique?
My build sheet has the code z82 for hd trailerling equipment
I can see there is a separate small cooler in front of the radiator center , as well as a tall narrow one driver side
I have read that the tran and oil cooler in the k5l hd cooling are the only difference, some also stating a brake controller is included. In fact when i look it up it includes 2 sub-codes one for oil cooler one for tranny cooler
3a)Is the k5l only the tran/oil cooler?
3b)Is this something people would commonly get installed after so that its not on build sheet/glove box?
3c)Is k5l and z82 the same thing on a 2010 suburban? what are the differences?!
Its very frustrating to have the dealership sales guy, manual, local dealership mechanic, unverifiable internet sources, and the view through your grill all tell you something different.
I was thinking of adding another cooler in series in the case the one I have is too small or not equivalent to the k5l cooling
I live in southern Ontario and winter temperatures can stay at -20cel for a few weeks?
4a)Is over-cooling a problem at that temperature?
4b)better to add one with a remote switch fan /temperature bypass?(if so any suggestions?)
4c)Can the stock battery and alternate handle an additional fan easily?
Assume I add a large passive cooler in series with the one there now right in front of the radiator on the passenger side
4d)how does this extra heat dissipated almost right into the radiator affect the rest of the engine?!/can it be vented(is that a thing?)
I dont think i have a brake controller, a mechanic at my local dealership advised that one of the cables (7th pin aux? (according to internets research)) would have been hooked up if I had it.
5)How can I check if I have one, I currently dont have a trailer to test with and i have also read it might not give any signal unless you are moving?
Same Mechanic: also recommended "They are beasts, you can do a 6000lb trailer just fine I wouldnt change anything"
He also was not able to see the tranny cooler through the grill perhaps due to lighting conditions and assumed it wasnt there.
ok.
Axle ratio code is gu4 for 3.08
6a)Any chance this is wrong or has been changed
6b)is there a rpm/speed reference to confirm?
6c) not worth changing for the amt i plan to tow yes?
According to the manual:
1500 Series 4WD Long Wheel Base
ratio-max-gcvw
3.08-5,000 lbs (2 268 kg)-11,000 lbs (4 990 kg)
3.42-5,400 lbs (2 449 kg)-11,500 lbs (5 216 kg)
K5L HD Cooling Pkg 3.42-7,900 lbs (3 583 kg)-14,000 lbs (6 350 kg)
7)If you have k5l (or equivalent?) cooling and braking but a 3.08 ratio, would you just subtract the difference from the 3.42 ratio for 7500 lbs max and 13500 GCVW
I understand it might not be so linear.
tried filling in "changing gears" online travel trailer weight calculator
8)What is the weight of the rear axle RGAW, i cant find this anywhere!
Stupid question time:
9a)I have been assuming long wheelbase, nothing has indicated to me which vehicles fall into which category
9b)Tow in 2wd all the time? 4x4 for when your pulling a boat out and up a wet ramp only?
9c)Are suspension "upgrades" like
"Roadmaster Active Suspension Custom Leaf Spring Enhancement Kit"
or
"Timbren Rear Suspension Enhancement System"
or
"Coil SumoSprings Custom Helper Springs for Coil Spring Suspension"
worth it/help handling and sway?
9d)Do the above interfere with a weight distribution hitch w sway control in any way?
9e)can you use all 3 + weight dist hitch at once?
OK so on to this "weak" rear axle i have read about: assuming tranny is nice and cool
10)it is worth the swap to 3.42 considering how infrequently i will tow?
Heard the rear diff gets too hot and burns out, not sure what that actually means
11a)Is that just the oil cooks off and no longer provides protection?
11b)Is there a differential cooler kit that someone can recommend?
12a) Can you replace front and rear diff/axles with ones from a 2500? or another compatible vehicle with beefier numbers?
12b) Im guessing not but if so any additional suspension you would do at the same time?
13)$350 for a tuner? eco mode when not towing, 25 more hp and torque + towing mode 3-4 times per year?Do it?
14) Please recommend to me anything that is a weak link i might have missed
15) What else would you do thats not on my radar?
16) Any aftermarket upgrades engineered to increase capacities in any way?
Thanks for your thorough and fact based replies in advance
New to towing and trucks in general, not new to logic and numbers. I have found and been even handed some incongruent information about the towing capacity derived from the options on my 2010 Suburban.
Here is what i got, sorry if its a novel but theres a lot i would like to clear up. I'll number my questions so you can pick and chose your replies if your kind enough to share your knowledge.
I purchased private 2010 suburban lt through a dealer at 124k km (so the private seller gets tax off his new car i assume?) it seems to be in great interior/exterior/mechanical shape so far.
Intent: This is to be the wife's infrequently used daily drive while on mat-leave, and the tow vehicle for 3 or 4 camping trips every summer from here on out, estimated driving distance ~500km each way. trailer not yet purchased, weight estimated at ~5-6k lbs (dont need to put water in it until at campground). Family weight + gear in car ~600lbs
I would like to install the most effective options to get the tow capacity to its highest engineered standard, not so I can tow anything pushing those limits but to create as large a gap as possible and increase the stability and safety those few times i will be towing.
So the dealer looked up the build sheet, ran the codes though some program which compared it to a 2012 yukon and told me that while it has the tow package, the towing capacity is 4600lbs (which is coincidentally the RGAWR)
1)The lowest rating is 5000lbs in the manual, why would he have a different number in the computer?
2)Are RPO code completely reliable and unique?
My build sheet has the code z82 for hd trailerling equipment
I can see there is a separate small cooler in front of the radiator center , as well as a tall narrow one driver side
I have read that the tran and oil cooler in the k5l hd cooling are the only difference, some also stating a brake controller is included. In fact when i look it up it includes 2 sub-codes one for oil cooler one for tranny cooler
3a)Is the k5l only the tran/oil cooler?
3b)Is this something people would commonly get installed after so that its not on build sheet/glove box?
3c)Is k5l and z82 the same thing on a 2010 suburban? what are the differences?!
Its very frustrating to have the dealership sales guy, manual, local dealership mechanic, unverifiable internet sources, and the view through your grill all tell you something different.
I was thinking of adding another cooler in series in the case the one I have is too small or not equivalent to the k5l cooling
I live in southern Ontario and winter temperatures can stay at -20cel for a few weeks?
4a)Is over-cooling a problem at that temperature?
4b)better to add one with a remote switch fan /temperature bypass?(if so any suggestions?)
4c)Can the stock battery and alternate handle an additional fan easily?
Assume I add a large passive cooler in series with the one there now right in front of the radiator on the passenger side
4d)how does this extra heat dissipated almost right into the radiator affect the rest of the engine?!/can it be vented(is that a thing?)
I dont think i have a brake controller, a mechanic at my local dealership advised that one of the cables (7th pin aux? (according to internets research)) would have been hooked up if I had it.
5)How can I check if I have one, I currently dont have a trailer to test with and i have also read it might not give any signal unless you are moving?
Same Mechanic: also recommended "They are beasts, you can do a 6000lb trailer just fine I wouldnt change anything"
He also was not able to see the tranny cooler through the grill perhaps due to lighting conditions and assumed it wasnt there.
ok.
Axle ratio code is gu4 for 3.08
6a)Any chance this is wrong or has been changed
6b)is there a rpm/speed reference to confirm?
6c) not worth changing for the amt i plan to tow yes?
According to the manual:
1500 Series 4WD Long Wheel Base
ratio-max-gcvw
3.08-5,000 lbs (2 268 kg)-11,000 lbs (4 990 kg)
3.42-5,400 lbs (2 449 kg)-11,500 lbs (5 216 kg)
K5L HD Cooling Pkg 3.42-7,900 lbs (3 583 kg)-14,000 lbs (6 350 kg)
7)If you have k5l (or equivalent?) cooling and braking but a 3.08 ratio, would you just subtract the difference from the 3.42 ratio for 7500 lbs max and 13500 GCVW
I understand it might not be so linear.
tried filling in "changing gears" online travel trailer weight calculator
8)What is the weight of the rear axle RGAW, i cant find this anywhere!
Stupid question time:
9a)I have been assuming long wheelbase, nothing has indicated to me which vehicles fall into which category
9b)Tow in 2wd all the time? 4x4 for when your pulling a boat out and up a wet ramp only?
9c)Are suspension "upgrades" like
"Roadmaster Active Suspension Custom Leaf Spring Enhancement Kit"
or
"Timbren Rear Suspension Enhancement System"
or
"Coil SumoSprings Custom Helper Springs for Coil Spring Suspension"
worth it/help handling and sway?
9d)Do the above interfere with a weight distribution hitch w sway control in any way?
9e)can you use all 3 + weight dist hitch at once?
OK so on to this "weak" rear axle i have read about: assuming tranny is nice and cool
10)it is worth the swap to 3.42 considering how infrequently i will tow?
Heard the rear diff gets too hot and burns out, not sure what that actually means
11a)Is that just the oil cooks off and no longer provides protection?
11b)Is there a differential cooler kit that someone can recommend?
12a) Can you replace front and rear diff/axles with ones from a 2500? or another compatible vehicle with beefier numbers?
12b) Im guessing not but if so any additional suspension you would do at the same time?
13)$350 for a tuner? eco mode when not towing, 25 more hp and torque + towing mode 3-4 times per year?Do it?
14) Please recommend to me anything that is a weak link i might have missed
15) What else would you do thats not on my radar?
16) Any aftermarket upgrades engineered to increase capacities in any way?
Thanks for your thorough and fact based replies in advance
September 24th, 2018, 10:07 PM
#2
You're totally overthinking this. But unfortunately, the 3.08 axle makes your truck a dog for towing. It's a mileage ratio, not a towing ratio. I call it the "soccer mom gearing." Yes, probably too expensive to regear for the number of times you're using it to tow. And you'd have to regear both axles.
Also, regearing won't make the axle stronger. It's the construction of the axle, not the ratio, that makes it weak. It's a semi-floater, as compared to the full floater on the 3/4-ton trucks. Google the difference.
No, 1500 and 2500 components are not swappable. Under the body, they're two totally different trucks.
Yes, tow in 2wd.
You don't have a 4600-lb rear axle weight rating. You have a 4200-lb rear axle weight rating. Look for this sticker in the driver's door jam, this is my 2500:
Most dealerships and most salespeople know nothing about towing ratings. And RV dealerships aren't any better. When I rolled up in my '01 half-ton Suburban, the salesman said, "Pick anything you want - that beast can tow anything."
Regards to RPO codes - forget about the build sheet, check the codes on the sticker in the glove box.
Looking at my truck:
The trans cooler is the small one in the center, the engine oil cooler is the small vertical one on the driver's side. But the axle ratio is going to dictate your towing capacity, not the presence of coolers.
Brake controller - if you don't have an integral brake controller on the dash, you buy a pigtail that plugs in underneath the dash, and then you wire that to the aftermarket brake controller. I did that for both of my trucks - easy peasy thanks to youtube. The Tekonsha P3 is the undisputed king of brake controllers. Don't cheap out on such a critical item.
Bottom line - go out and buy a half-ton towable travel trailer. Dry weight around 4500-5000 lbs. Here's my first trailer, with my half-ton Burb:
Pulled that rig from Michigan to Florida several times, no issues.
Yes, the rear axle is the weak link. Go out and buy a new differential cover with cooling fins on it. Load up the family and have fun. You're not going to fry your rear axle driving a few hundred miles a few times a year.
So, to sum up:
1) Buy pigtail and Tekonsha P3.
2) Buy aftermarket diff cover with cooling fins
3) Buy half-ton towable trailer, 4500-5000 dry weight.
4) Load up family and have fun.
Also, regearing won't make the axle stronger. It's the construction of the axle, not the ratio, that makes it weak. It's a semi-floater, as compared to the full floater on the 3/4-ton trucks. Google the difference.
No, 1500 and 2500 components are not swappable. Under the body, they're two totally different trucks.
Yes, tow in 2wd.
You don't have a 4600-lb rear axle weight rating. You have a 4200-lb rear axle weight rating. Look for this sticker in the driver's door jam, this is my 2500:
Most dealerships and most salespeople know nothing about towing ratings. And RV dealerships aren't any better. When I rolled up in my '01 half-ton Suburban, the salesman said, "Pick anything you want - that beast can tow anything."
Regards to RPO codes - forget about the build sheet, check the codes on the sticker in the glove box.
Looking at my truck:
The trans cooler is the small one in the center, the engine oil cooler is the small vertical one on the driver's side. But the axle ratio is going to dictate your towing capacity, not the presence of coolers.
Brake controller - if you don't have an integral brake controller on the dash, you buy a pigtail that plugs in underneath the dash, and then you wire that to the aftermarket brake controller. I did that for both of my trucks - easy peasy thanks to youtube. The Tekonsha P3 is the undisputed king of brake controllers. Don't cheap out on such a critical item.
Bottom line - go out and buy a half-ton towable travel trailer. Dry weight around 4500-5000 lbs. Here's my first trailer, with my half-ton Burb:
Pulled that rig from Michigan to Florida several times, no issues.
Yes, the rear axle is the weak link. Go out and buy a new differential cover with cooling fins on it. Load up the family and have fun. You're not going to fry your rear axle driving a few hundred miles a few times a year.
So, to sum up:
1) Buy pigtail and Tekonsha P3.
2) Buy aftermarket diff cover with cooling fins
3) Buy half-ton towable trailer, 4500-5000 dry weight.
4) Load up family and have fun.
Last edited by intheburbs; September 24th, 2018 at 10:24 PM.
September 24th, 2018, 10:21 PM
#3
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You're totally overthinking this. But unfortunately, the 3.08 axle makes your truck a dog for towing. It's a mileage ratio, not a towing ratio. Yes, probably too expensive to regear for the number of times you're using it to tow. And you'd have to regear both axles.
Also, regearing won't make the axle stronger. It's the construction of the axle, not the ratio, that makes it weak. It's a semi-floater, as compared to the full floater on the 3/4-ton trucks. Google the difference.
No, 1500 and 2500 components are not swappable. Under the body, they're two totally different trucks.
Yes, tow in 2wd.
You don't have a 4600-lb rear axle weight rating. You have a 4200-lb rear axle weight rating. Look for this sticker in the driver's door jam, this is my 2500:
Most dealerships and most salespeople know nothing about towing ratings. And RV dealerships aren't any better. When I rolled up in my '01 half-ton Suburban, the salesman said, "Pick anything you want - that beast can tow anything."
Regards to RPO codes - forget about the build sheet, check the codes on the sticker in the glove box.
Looking at my truck:
The trans cooler is the small one in the center, the engine oil cooler is the small vertical one on the driver's side. But the axle ratio is going to dictate your towing capacity, not the presence of coolers.
Bottom line - go out and buy a half-ton towable travel trailer. Dry weight around 4500-5000 lbs. Here's my first trailer, with my half-ton Burb:
Pulled that rig from Michigan to Florida several times, no issues.
Yes, the rear axle is the weak link. Go out and buy a new differential cover with cooling fins on it. Load up the family and have fun. You're not going to fry your rear axle driving a few hundred miles a few times a year.
Also, regearing won't make the axle stronger. It's the construction of the axle, not the ratio, that makes it weak. It's a semi-floater, as compared to the full floater on the 3/4-ton trucks. Google the difference.
No, 1500 and 2500 components are not swappable. Under the body, they're two totally different trucks.
Yes, tow in 2wd.
You don't have a 4600-lb rear axle weight rating. You have a 4200-lb rear axle weight rating. Look for this sticker in the driver's door jam, this is my 2500:
Most dealerships and most salespeople know nothing about towing ratings. And RV dealerships aren't any better. When I rolled up in my '01 half-ton Suburban, the salesman said, "Pick anything you want - that beast can tow anything."
Regards to RPO codes - forget about the build sheet, check the codes on the sticker in the glove box.
Looking at my truck:
The trans cooler is the small one in the center, the engine oil cooler is the small vertical one on the driver's side. But the axle ratio is going to dictate your towing capacity, not the presence of coolers.
Bottom line - go out and buy a half-ton towable travel trailer. Dry weight around 4500-5000 lbs. Here's my first trailer, with my half-ton Burb:
Pulled that rig from Michigan to Florida several times, no issues.
Yes, the rear axle is the weak link. Go out and buy a new differential cover with cooling fins on it. Load up the family and have fun. You're not going to fry your rear axle driving a few hundred miles a few times a year.
I was hoping you would reply and thanks for sharing the pic with your setup and fam. Yes the door say 4200 my mistake. I may be overthinking things but I want to make sure I dont overlook something of consequence , i have a 2yo and come dec we're expecting 2 more in one shot. Due diligence. If you don't mind i would like to further pick your brain, much less q's this time
-Should i add another in-line tranny cooler or not worth it?
-Is 5.5-6k dry what you would consider too much? 3-4x per year, ~500km (310miles) each way.
-I would appreciate a recommendation on diff cap for cooling purposes (I entirely overlooked that aspect but say it in a few of your posts)
Regards
September 25th, 2018, 5:09 PM
#4
Separately, if you notice in the pic above, we have twins as well. Daughter was 2 1/2 when the boys were born. The first two years sucked, after that it was awesome. They're all in college now. 
You should start saving. Now.
Do you have the factory trans cooler? If not, one would probably help. But again, a few hundred miles really won't stress anything out. Worst case, if you start getting elevated transmission temps on your first few trips, say above 220° or so, you can always install it then.
I don't really have a differential cover to recommend. I never put one on my half-ton (while destroying three rear axles), and my 2500 already has one. Any one for that rear axle, aluminum, cooling fins, should do the trick. You have the 9.5" 14-bolt semifloater.
Once I got close to 7000 lbs, stuff started breaking. Dry weight is a little misleading. Figure you can add about 1000 lbs to your trailer weight, once it's packed and loaded up for a trip. So a 5.5-6k dry weight will probably be closer to 6.5k-7k. A properly-balanced trailer has about 13% of its weight on the tongue, which would be about 850-900 lbs of tongue weight. Add your 600 lbs of family and gear (and don't forget more weight as the kids grow - my family is 900 lbs), and the weight of the hitch itself, and you're just about maxed out on your payload. If you check the sticker on your door, I'll wager your payload is between 1500 and 1600 lbs. You'll also be maxing out that rear axle weight. Check this sticker in the door jam to confirm your payload:
You should start saving. Now.Do you have the factory trans cooler? If not, one would probably help. But again, a few hundred miles really won't stress anything out. Worst case, if you start getting elevated transmission temps on your first few trips, say above 220° or so, you can always install it then.
I don't really have a differential cover to recommend. I never put one on my half-ton (while destroying three rear axles), and my 2500 already has one. Any one for that rear axle, aluminum, cooling fins, should do the trick. You have the 9.5" 14-bolt semifloater.
Once I got close to 7000 lbs, stuff started breaking. Dry weight is a little misleading. Figure you can add about 1000 lbs to your trailer weight, once it's packed and loaded up for a trip. So a 5.5-6k dry weight will probably be closer to 6.5k-7k. A properly-balanced trailer has about 13% of its weight on the tongue, which would be about 850-900 lbs of tongue weight. Add your 600 lbs of family and gear (and don't forget more weight as the kids grow - my family is 900 lbs), and the weight of the hitch itself, and you're just about maxed out on your payload. If you check the sticker on your door, I'll wager your payload is between 1500 and 1600 lbs. You'll also be maxing out that rear axle weight. Check this sticker in the door jam to confirm your payload:
October 11th, 2018, 9:00 PM
#5
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Hello Intheburbs
Pardon the delay in reply, very busy with house preps and got sent away for work for a week. I suspected the two int he pic might be twins, thats awesome thanks for sharing. My daughter will be 2 1/2 at the time we're expecting them as well.
So I do have the factory trans cooler and the oil cooler on the drivers side, I will keep an eye on the temps but i guess it should be fine.
I have not been able to find a straight answer, what other suv's or trucks have interchangeable parts with the 2010 Suburban? I think for the most part its the same generation Tahoe/Yukon/Yukon XL, how about the the Cadillacs/Denalis or Silverado/Sierra ?
Thanks again for your posts and advice.
Pardon the delay in reply, very busy with house preps and got sent away for work for a week. I suspected the two int he pic might be twins, thats awesome thanks for sharing. My daughter will be 2 1/2 at the time we're expecting them as well.
So I do have the factory trans cooler and the oil cooler on the drivers side, I will keep an eye on the temps but i guess it should be fine.
I have not been able to find a straight answer, what other suv's or trucks have interchangeable parts with the 2010 Suburban? I think for the most part its the same generation Tahoe/Yukon/Yukon XL, how about the the Cadillacs/Denalis or Silverado/Sierra ?
Thanks again for your posts and advice.
October 13th, 2018, 5:42 AM
#6
With regards to interchangeable parts... the GMT900 platform includes:
Chevy Tahoe/Suburban/Avalanche/Silverado
GMC Yukon/Yukon XL/Sierra
Cadillac Escalade/ESV/EXT
Denali is simply a trim level, not any specific model, and includes other non-GMT900 models. You can have a Yukon Denali, Sierra Denali, Acadia Denali, etc. The GMT900 Denalis are very similar to the equivalent Escalade models - meaning a Yukon XL Denali will be very close to an Escalade ESV.
Of course not all parts are interchangeable, but there is a lot of overlap.
Chevy Tahoe/Suburban/Avalanche/Silverado
GMC Yukon/Yukon XL/Sierra
Cadillac Escalade/ESV/EXT
Denali is simply a trim level, not any specific model, and includes other non-GMT900 models. You can have a Yukon Denali, Sierra Denali, Acadia Denali, etc. The GMT900 Denalis are very similar to the equivalent Escalade models - meaning a Yukon XL Denali will be very close to an Escalade ESV.
Of course not all parts are interchangeable, but there is a lot of overlap.
