3.42 to 4.10

[AH64ID]

but I wonder why the GVWR of the 3500 isn't a little higher with the stronger transmission...

Same reason I am "rated" to tow more than the DRW variant of my truck... bean counters and executives don't look at that stuff.

 

[gsbrockman]

I noticed that too... really makes you wonder. We all know that GCVWR of the 2500 is artificially determined by the 10K rating for a class 2B truck registration. The 3500 with the Aisin is certainly a more stout driveline than the 68RFE, but I wonder why the GVWR of the 3500 isn't a little higher with the stronger transmission...

If comparing to the 3500 SRW.....the tires are the limiting factor I'd imagine. 11,700 GVWR crew cab short bed 4wd.....12,300 GVWR crew cab long bed 4wd.

 

[dfb]

I know the Dually is higher rated for more load in the bed.. However, since the dually weighs more it should have a lower trailer tow rating ......... NOT WEIGHT Capacity in the bed.. That is MOOT on PULLING... If both pin weight are 3000lbs then the SRW should have a higher trailer pulling capacity due to the less weight of the truck on the SRW... The GVWR on the Mega Cab 3500 is 12300 lbs... the dually is 14000 due to the extra tires. But extra tires should NOT give a truck a Higher Pulling Capacity.... I think they got this "Backwards".. Just like the 68RFE has a higher rated payload because the truck's weight is less... However, the Chart is showing a truck that Weighs more having a higher tow capacity by 3300 lbs....BTW,,, this truck has a WEIGHT OF 8900lbs!!!this leaves 3400lbs to put in the truck.... Thanks gang...

 

[dfb]

On the 3;42 vs 410s... RPMs are RPMs.... it does not matter ...The engine does not see the difference...Overdrives don't change the ring and pinion, however, the engine will see it this way...

 

[AH64ID]

I know the Dually is higher rated for more load in the bed.. However, since the dually weighs more it should have a lower rating ......... NOT WEIGHT Capacity in the bed.. That is MOOT on PULLING... If both pin weight are 3000lbs then the SRW should have a higher trailer pulling capacity due to the less weight of the truck on the SRW...

There are many reasons why, but the primary reason will likely deal with SAE J2807. A DRW has different test standards than a SRW and those test standards are "easier". Basically they can be SAE J2807 compliant with the exact same drivetrain at a higher weight.


SAE J2807 involves several tests and here are the differences from SRW to DRW.

Acceleration.
0-30 mph: SRW is given 12 seconds and DRW is given 14 seconds.
40-60: SRW is given 18 seconds and DRW is given 21 seconds.
0-60: SRW is given 30 seconds and DRW is given 35 seconds.

Grade. Trucks must climb the Davis grade with a minimum ambient temp of 100°F. SRW's have to maintain 40 mph, while DRW's only have to maintain 35 mph.

This is why the GCWR and trailer ratings are different.

My 05 is rated like you mentioned, as both the SRW and DRW have the same GCWR.

 

[Newsa]

I know the Dually is higher rated for more load in the bed.. However, since the dually weighs more it should have a lower trailer tow rating ......... NOT WEIGHT Capacity in the bed.. That is MOOT on PULLING... If both pin weight are 3000lbs then the SRW should have a higher trailer pulling capacity due to the less weight of the truck on the SRW... The GVWR on the Mega Cab 3500 is 12300 lbs... the dually is 14000 due to the extra tires. But extra tires should NOT give a truck a Higher Pulling Capacity.... I think they got this "Backwards".. Just like the 68RFE has a higher rated payload because the truck's weight is less... However, the Chart is showing a truck that Weighs more having a higher tow capacity by 3300 lbs....BTW,,, this truck has a WEIGHT OF 8900lbs!!!this leaves 3400lbs to put in the truck.... Thanks gang...

I have a hunch why this is. Let's say a SRW is cornering fast pullng a load and a DRW is taking the same corner at the same speed pulling the same load.

Compare the rear tire sidewall flex when cornering of the 2 vehicles. I think the DRW will have significantly more stability and keep more tread on the road?

 

[AH64ID]

Weight capacity in the bed plays a big part of trailer weight.

Lets look at some figures.

If both pin weights are 3,000 lbs then the trailer should only weigh 12,000-15,000 lbs and both the SRW and DRW are rated to pull it.

A 20K lb trailer should have a pin weight of 4,000 to 5,000 lbs. That is more than a SRW can handle, once you install a hitch, stuff in the cab, etc. This is why the payload matters.

Yes the 2016 MC, 4x4, SRW has an advertised payload of 4,130 with the Aisin; however, there is only 3,839 lbs to spare on the rear axle curb weight. By the time you add a hitch and a driver over 150 lbs, gear in the cab, floor mats, etc that is going to be down around 3,500 lbs of usable load on the rear axle. Cummins12V98 can post the exact figures, but IIRC only about 150lbs of his 5K pin weight goes to the front axle. That is 3% which gives you the capability of having approx 3,600lbs of pin weight. That should be a 14,400 to 18,000 lb trailer. Based on the SAE J2807 certification the truck couldn't meet the standards above 25,300lbs so you get a 16,660 lb tow rating.. which is doable with the weight limits of the SRW truck.

In theory the Aisin should always be rated to tow more than the 68RFE, just as a DRW should be rated to tow more than a SRW... but sometimes when you put engineers, lawyers, and SAE standards into the mix you get what you get...

Additionally did you notice that the SRW and DRW 68RFE have the same GCWR, so the SRW is actually rated to tow more given the same gears, despite the reduced times allowed in SAE J2807.

The AS69RC has different GCWR's DRW vs SRW, likely due to the improved gearing and thus acceleration tests with the slower required times of J2807.

What does that tell you about the confidence in the Aisin vs 68RFE by the engineers??

Besides, who really cares about GVWR and GCWR anyhow?

 

[dfb]

There are many reasons why, but the primary reason will likely deal with SAE J2807. A DRW has different test standards than a SRW and those test standards are "easier". Basically they can be SAE J2807 compliant with the exact same drivetrain at a higher weight.


SAE J2807 involves several tests and here are the differences from SRW to DRW.

Thank You for the explanation. So, really the SRW can tow the Same as the DRW??? 20330 pounds.....
12345678963
Acceleration.
0-30 mph: SRW is given 12 seconds and DRW is given 14 seconds.
40-60: SRW is given 18 seconds and DRW is given 21 seconds.
0-60: SRW is given 30 seconds and DRW is given 35 seconds.

Grade. Trucks must climb the Davis grade with a minimum ambient temp of 100°F. SRW's have to maintain 40 mph, while DRW's only have to maintain 35 mph.

This is why the GCWR and trailer ratings are different.

My 05 is rated like you mentioned, as both the SRW and DRW have the same GCWR.

So, in theory the SRW can tow the same and not hurt a thing.. Thanks for the reply..

 

[dfb]

I have a hunch why this is. Let's say a SRW is cornering fast pullng a load and a DRW is taking the same corner at the same speed pulling the same load.

Compare the rear tire sidewall flex when cornering of the 2 vehicles. I think the DRW will have significantly more stability and keep more tread on the road?

This on the surface makes sense... however, I have lived in snow country since I was 16.. Had a 73 Firebird with FAT MEATS on the back G-60-15s.. The Wider tire road more on top of the snow and did not BITE in like a narrower tire... There is less PSI on a Wider or in this case two tiries... You may be right.... tho.... Thanks....

 

[AH64ID]

So, in theory the SRW can tow the same and not hurt a thing.. Thanks for the reply..

In theory, if you can support the trailer on your SRW wheels and tires.

The tires are rated for more than 3500 lbs each, but the wheels are only rated for 3500 lbs. 7K lbs on the rear axle is going to be your limit to towing.

 

[dfb]

Exactly, Nick. The obvious answer is the 12,300 GVWR of the SRW vs. the 14,000 GVWR of the DRW. 1,700 lbs more of pin weight, cargo or passengers can be utilized in the DRW. An oddity dfb may have overlooked is the towing capacity of a 4x4 MegaCab SRW is more with the 68RFE vs the AISIN (16,800 vs. 16,660). Apparently there's 140 lbs more "guts" in an AISIN equipped truck----and subsequently 140 lbs less towing capacity.

The AISIN really shines with 3.73's over 3.42's and it shines most with 4.10's over 3.73's. When comparing all DRW trucks with 3.73's or 4.10's, the AISIN shines quite alot more over the 68RFE. The AISIN shines less in the SRW applications---where it is actually under utilized, IMO.

Great INFO... thank You!

 

[dfb]

In theory, if you can support the trailer on your SRW wheels and tires.

The tires are rated for more than 3500 lbs each, but the wheels are only rated for 3500 lbs. 7K lbs on the rear axle is going to be your limit to towing.

I see where this is going... Due to the larger 5ver size, there would be more pin weight that the SRW is not rated for as far as GVWR, RAWR.......is this correct?

 

[dfb]

In theory, if you can support the trailer on your SRW wheels and tires.

The tires are rated for more than 3500 lbs each, but the wheels are only rated for 3500 lbs. 7K lbs on the rear axle is going to be your limit to towing.

I see where this is going... Due to the larger 5ver size, there would be more pin weight that the SRW is not rated for as far as GVWR, RAWR.......is this correct? If this is the case, then going to a higher rated tire would bring up the tow rating since the rear axles are the same etc..?

 

[AH64ID]

I see where this is going... Due to the larger 5ver size, there would be more pin weight that the SRW is not rated for as far as GVWR, RAWR.......is this correct? If this is the case, then going to a higher rated tire would bring up the tow rating since the rear axles are the same etc..?

Basically yes that is correct.

The tires aren't your limit thou, the wheels are.

I just looked at the specs on your sig trailer...

It simply appears you have too much trailer for your truck and are trying to justify it on here... and no, I am not only talking about the published ratings.

Have you put your setup on the scale yet?

 

[dfb]

I will when the RV gets out of the shop.... weighed the truck as it sits with us in it...8900lbs....Leaves a 3400 capacity...

 

[gsbrockman]

I will when the RV gets out of the shop.... weighed the truck as it sits with us in it...8900lbs....Leaves a 3400 capacity...

Are the specs listed here fairly representative of the RV you own???

https://lakeshore-rv.com/keystone-rv/montana/2015-montana-3610rl-floor-plan/

If so....it's already at 2,905 lbs hitch weight---dry. If you have 3,400 capacity---I hope that includes your hitch installed. Throw a few items in the truck, and start plugging away at the RV's 3,975 lbs of cargo capacity....and you'll be over sooner than you think.

 

[dfb]

Are the specs listed here fairly representative of the RV you own???

https://lakeshore-rv.com/keystone-rv/montana/2015-montana-3610rl-floor-plan/

If so....it's already at 2,905 lbs hitch weight---dry. If you have 3,400 capacity---I hope that includes your hitch installed. Throw a few items in the truck, and start plugging away at the RV's 3,975 lbs of cargo capacity....and you'll be over sooner than you think.

Your Good!!! Thanks.. Yes this is the RV... I believe the truck and trailer combo is fine as the hitch only weighs 32lbs!!!! The Weight was with the hitch in, liner, everything... 8900 lbs.. so 2905 pin weight that leave nearly 500 lbs.. I could however go to a higher hitch height if it is too close thereby losing some Pin weight... Probably a lot... The thing I don't get is WHY Chrysler would build a Heavy Duty (Medium Duty) Truck and make it a Short bed??? WHY???? The 2015 has 385 hp, and 865 lb feet of torque!!! this is a tow monster!! My 04.5 Was a Dually, 6 speed NV5600 trans with 4:10s... The Old truck had a GVWR of 12200... New truck GVW is 12300 SRW!! Pulling a grade out of town the old truck pulled it at 52 mph with this RV.. Pulling this RV with the New truck it does 65 mph EASY up the grade... So I know I don't have too much trailer... If it were a TETON or Mobile Suites then YES not enough truck..Old truck would ride on the overload springs with the RV.. Air bags this new truck rides Level.. Pulls Great... The GVWR on the Montana I have is 16000.. Truck is rated for 16660.. I have never seen a trailer close to the GVWR... Remember, this rating include people inside when parked as well... Water, trash, food, battery or batteries.. everything... But I will be weighing the REAR and the truck and trailer together...

 

[dfb]

Basically yes that is correct.

The tires aren't your limit thou, the wheels are.

I just looked at the specs on your sig trailer...

It simply appears you have too much trailer for your truck and are trying to justify it on here... and no, I am not only talking about the published ratings.

Have you put your setup on the scale yet?

So If I go with the Alcoa 19.5 this may cure the issue?
I don't have an issue with the truck and trailer I have now... Just why the dually could pull 3300 more... Truck pulls trailer better than my 04 Dually with 4!0s... It silently and effortlessy pull great..Really, almost like no load...

 

[dfb]

Funny my old truck would tach 1900 rpms at 60.. the new one tachs 1250 at 60// MPG are at 19.5 pure hi way.... up and down hills... nice...

 

[dfb]

old truck ......