which gear ratio to use in my Chevy

[Chuck Oppermann]

I would actually weigh the trailer full with clothes and water etc. just like you were going to use it. Manufacturer weights, as far as I know, don't add on some options, and they add up really fast. That might be a 10,000# trailer when you get done, and with a 7800# tow capacity truck, you will have a miserable time. You will be white knuckling it all the time and it would not be fun, plus it would be unsafe.

 

[MossRoad]

Moved to trailers and transportation forum.

 

[Diamondpilot]

I have a 2005 Chevy Surburban 2 wheel drive 1/2 ton with a 5.3 L. motor. My truck currently has 3.42 gear ratio in it. I am towing a 32 ft travel trailer that has a empty weight of 7400 lbs. I am going to upgrade the diff. gears, however I can't decide between a 3.73 gear or a 4.10 gear ratio. The transmission is a 4L60. I would love to hear some feed back...

According to my book a 1500 Suburban made in 2005 only came with 2 gear ratios available. The 3.42 like you have had a tow rating of 7,400# and the optional 4.10 gear ratio had a 8,400# tow rating. I would imagine you will be able to get the 4.10 gear set from your GM dealer to do a factory upgrade. Just be aware on a modern truck its more difficult than just swapping the gears.

You must have the computer either replaced or reprogrammed and there may need to be some slight changed done to the tranny. Also a larger tranny cooler and power steering cooler may need to be added.

The legal end of this is no matter what you do to your Suburban its max tow rating was set at the factory along with the GVWR and GCWR.

If you are unfamiliar the GVWR is the (gross vehicle wheel rating ) or max load that can be on the truck. This includes the truck itself, passengers, luggage, and hitch tongue weight. IE the weight that is carried on the trucks axles. This max GVWR can be found on the door pillar on the drivers side. You will have a rating for the truck along with a rating for each axle. The axle ratings usually do not equal the GVWR. For example lets say the GVWR is 7700# but you may have a 4,500# rear axle and a 3,800# front axle. The important part is to not exceed the max GVWR while not exceeding either axle at the same time.

GCWR is ( gross combined wheel rating ) and this is in the manual of your truck. It will simply be the max weigh both truck and trailer can weigh if pulled across the scales. Again you must be inside this and not exceed the GVWR or any axle rating while doing so.

Hope this helps. You can change gears, up the HP, put in a bigger engine, turbo, ect but its not going to LEGALLY make it tow more. So at the end of the day no matter what you do you can not upgrade the tow rating of your truck legally.

Chris

 

[Diamondpilot]

I would actually weigh the trailer full with clothes and water etc. just like you were going to use it. Manufacturer weights, as far as I know, don't add on some options, and they add up really fast. That might be a 10,000# trailer when you get done, and with a 7800# tow capacity truck, you will have a miserable time. You will be white knuckling it all the time and it would not be fun, plus it would be unsafe.

Very true. I know were are talking trailers here but the worst I have seen is a boat that was listed 9,500# and I allowed 3,000# for the trailer. It was to be 12,500# when I bought it. I took delivery and had it weighed that day and it was 15,600# with all the options it had on it. I had a weight slip on the trailer and it was 2,800# without the spare tire so the boat had gained about 3,000#.

Chris

 

[deerefan]

According to my book a 1500 Suburban made in 2005 only came with 2 gear ratios available. The 3.42 like you have had a tow rating of 7,400# and the optional 4.10 gear ratio had a 8,400# tow rating. I would imagine you will be able to get the 4.10 gear set from your GM dealer to do a factory upgrade. Just be aware on a modern truck its more difficult than just swapping the gears.

You must have the computer either replaced or reprogrammed and there may need to be some slight changed done to the tranny. Also a larger tranny cooler and power steering cooler may need to be added.

The legal end of this is no matter what you do to your Suburban its max tow rating was set at the factory along with the GVWR and GCWR.

If you are unfamiliar the GVWR is the (gross vehicle wheel rating ) or max load that can be on the truck. This includes the truck itself, passengers, luggage, and hitch tongue weight. IE the weight that is carried on the trucks axles. This max GVWR can be found on the door pillar on the drivers side. You will have a rating for the truck along with a rating for each axle. The axle ratings usually do not equal the GVWR. For example lets say the GVWR is 7700# but you may have a 4,500# rear axle and a 3,800# front axle. The important part is to not exceed the max GVWR while not exceeding either axle at the same time.

GCWR is ( gross combined wheel rating ) and this is in the manual of your truck. It will simply be the max weigh both truck and trailer can weigh if pulled across the scales. Again you must be inside this and not exceed the GVWR or any axle rating while doing so.

Hope this helps. You can change gears, up the HP, put in a bigger engine, turbo, ect but its not going to LEGALLY make it tow more. So at the end of the day no matter what you do you can not upgrade the tow rating of your truck legally.

Chris

Help me out a little here, Chris. My 11 Silverado, 4x4, 5.3 3.42 ratio has a 9500lb tow cap. but gvwr is 7000. So can I pull 9500 lbs or 7k or am I misinterpreting this?

 

[firefighter jim]

Help me out a little here, Chris. My 11 Silverado, 4x4, 5.3 3.42 ratio has a 9500lb tow cap. but gvwr is 7000. So can I pull 9500 lbs or 7k or am I misinterpreting this?

gvwr = weight of your vehicle plus what it can CARRY. Tow capacity is just that (how heavy a trailer your vehicle can pull). Also consider your gcwr (gross COMBINED weight rating) which, as the name implies, is the total weight amount of both vehicle and trailer.....................that figure will also be listed in your vehicles manual.

 

[Diamondpilot]

gvwr = weight of your vehicle plus what it can CARRY. Tow capacity is just that (how heavy a trailer your vehicle can pull). Also consider your gcwr (gross COMBINED weight rating) which, as the name implies, is the total weight amount of both vehicle and trailer.....................that figure will also be listed in your vehicles manual.

His answer is 100% correct. The 7,000# GVWR on your truck is the max weight that can be on the trucks axles. So lets say the truck weight 5,500# and you put you and a buddy in it at 200# each plus 100# of supplies in the bed the truck will be at 6,000#. Now if you hitch up a trailer you can add upto 1,000# for the tongue weight to keep the truck at 7,000# max as specified by the GVWR.

Now remember that that 9,500# tow capacity is best case. That is just a small guy in the truck, nothing in the bed, low option truck, ect.

Take my 08 Nissan Titan for example, very close to your truck. It has a advertised tow rating of 9,500# but I have weighed it and subtracted that weight from the GCWR and it leaves me 9,340# max tow rating. I did this with me in it, all my regular stuff in the truck, and 3/4 tank of fuel. My truck has every factory option plus a few extras that were dealer installed like a 2" lift, Detroit Front Locker, ect. Anyway, it lost 160# of tow rating because of this.

Chris

 

[yourspectra1970]

According to the door sticker the GVRW is 7000# with everything being original which it is not. I have added air bags to the rear. changed the air intake and reprogramed the computer the up the pony's.


So according to everything I read ( if I understand it correctly) if I put the 4.10 gears in it then that should increase the towing compacity ??

 

[Diamondpilot]

According to the door sticker the GVRW is 7000# with everything being original which it is not. I have added air bags to the rear. changed the air intake and reprogramed the computer the up the pony's.


So according to everything I read ( if I understand it correctly) if I put the 4.10 gears in it then that should increase the towing compacity ??

I am not trying to be a jerk here but go back and re-read what we posted. There is nothing you can do to increase the tow rating, only make it tow better. Changing the gear ratio is just another way to make it have more power. Ok, just feel like it. Just like adding the air bags made it handle the weight better it by no means allows you to haul more than the GVWR and changing the intake and running a program just frees up some of the hidden pony's. We used to do this with a 4 barrel carb, headers, ect.

Sounds like its time for a bigger truck. If you have had to add air bags thats the first clue.

There is the legal aspect here. Your truck has to weigh north of 6,000# and by the time you put your family and gear in it you are going to be near the GVWR. Now as soon as you put your trailer on the back you are exceeding the GVWR and with the weight of your trailer you are over the GCWR no matter what you do.

Chris

 

[RickB]

I am not trying to be a jerk here but go back and re-read what we posted. There is nothing you can do to increase the tow rating, only make it tow better. Chris

Classic case of someone asking a legitimate question then refusing to hear the answer.