Vehicle upgrades for RWD

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RamCamp1985

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I am looking for some advice. I currently have a 2013 Ram 2500 Tradesman 5.7 gasser with RWD. It has an open differential. This vehicle will only be used for towing my camper to WI state parks and we don’t plan on doing any boondocking in off road locations. Can I get your thoughts regarding upgrading the rear differential and if you think locking vs limited slip is a better option. None of the dealers in the area will touch it (one said it couldn’t be done). I did find a local shop that has experience. Thanks in advance!
 

tron67j

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My two cents, LSD is great. I had that in my 2WD 2500 and had no problems and that truck towed large trailers and 5th wheels for much of the time. Perhaps you could find a rear end out of a wreck, have it rebuilt, and then install. Good luck.
 

lpennock

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Detroit truetrac is the best choice for a daily driver. Totally transparent on road and gives excellent traction off road. Check with some 4wd shops. They should be able to do for about $1k.

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They call me DLD

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Mine is a 2011 Dodge Ram 2500 2WD 5.7 Hemi and has the 3.73 axle ratio and limited slip diff. If you are making a decision to go into the rear axle for a diff change, then maybe some thought needs to be given for an axle ratio. With the weight of the travel trailer and the frontal area (wind resistance) of this trailer, maybe a 4.10 ring and pinion should be considered.

Do you know what rear axle ratio you have?

Best part of 2WD is there only needs a gear swap on the rear axle.

Also, mine is a big horn that came with the 265 tire. Most tradesman came with the smaller 245 tire size in 2011. Not sure what your 2013 came equipped with, but a shorter tire makes the effective gear reduction better for a trailer towing weekend.
 
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RamCamp1985

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Thanks for the input, it’s greatly appreciated.

I have a 3.73 axle ratio on my truck. The equipment listing showed that it originally came with a 245 but when I bought it, 285 were on the truck. I’m thinking about changing to 4.10 but haven’t decided yet.
 
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RamCamp1985

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Just called a 4x4 shop and was quoted $2500 to install a LSD. Parts alone were over $1500. Seems high so I’ll keep checking around.
 

RLJ10X

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If you have a 5.7 in a 2500, and you're on the fence wether to go to 4.10s or not; let me help.

Go 4.10s. It's the gift that gives back every time you drive the truck. You can take all the mods to my truck, but if you take my 4.10s, I'm getting a new truck.

Talk to Matt @ Moe's. He is THE expert. He has everything you need, plus good advice, if needed. And he's just a cool cat.
 

engineering

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If you have a 5.7 in a 2500, and you're on the fence wether to go to 4.10s or not; let me help.

Go 4.10s. It's the gift that gives back every time you drive the truck. You can take all the mods to my truck, but if you take my 4.10s, I'm getting a new truck.

Talk to Matt @ Moe's. He is THE expert. He has everything you need, plus good advice, if needed. And he's just a cool cat.


MOE's has good prices too.
 

TheBaseModelGuy

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Hi People,

I don't mean to hijack a thread but i am in the market for a camper and just cant deal with the 4450 towing capacity on my 3.21 ratio truck, people on this thread seem to know about the subject. My question is: is upgrading the differential the only thing needed to increase the towing capacity of my 2020 v6 ram to 7000lbs?

again sorry for hijacking but I'm new to this forum and forums in general so I wasn't able to find an existing thread
 

engineering

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Hi People,

I don't mean to hijack a thread but i am in the market for a camper and just cant deal with the 4450 towing capacity on my 3.21 ratio truck, people on this thread seem to know about the subject. My question is: is upgrading the differential the only thing needed to increase the towing capacity of my 2020 v6 ram to 7000lbs?

again sorry for hijacking but I'm new to this forum and forums in general so I wasn't able to find an existing thread

Well, the topic of this thread is very generic so I don't think that is a Hijack.

The question you should ask is if the max legal towing capacity of the truck will change if you change the rear gears.

If you got the truck with 3.55 it gets a sticker giving it the legal capacity. You have the 3.21 capacity ratings on your stickers and that will not change if you swap gears. Obviously you get the mechanical benefit but if you were in an accident - the lawyers are just looking for a detail they can exploit and make you the liable party. Over weight capacity is a very common reason for accidents to occur - so you can count on that being scrutinized right away.
 

engineering

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GCWR is not on any sticker the last time I looked.

So, does the max legal trailer weight change with a gear change? I definitely don't claim expert knowledge here, looking to learn.

I feel like there are some stickers/stamps somewhere that indicate my truck is 3.21 - does that permanently lock in the max trailer weight? Even if GCWR is still under?

You can be over max towing weight and still under GCWR.
 

TheBaseModelGuy

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Well, the topic of this thread is very generic so I don't think that is a Hijack.

The question you should ask is if the max legal towing capacity of the truck will change if you change the rear gears.

If you got the truck with 3.55 it gets a sticker giving it the legal capacity. You have the 3.21 capacity ratings on your stickers and that will not change if you swap gears. Obviously you get the mechanical benefit but if you were in an accident - the lawyers are just looking for a detail they can exploit and make you the liable party. Over weight capacity is a very common reason for accidents to occur - so you can count on that being scrutinized right away.

I definitely plan on staying very close to my original towing limit regardless but I would very much rather "technically" have a towing capacity of 7000lbs rather than 4450lbs while towing a 4000lb dry weight camper. (which is what my budget allows anyway)
 

Travelin Ram

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This comes up often in some RV forums. I have yet to see a statute cited that restricts GCW for private vehicles. GVW yes.

Conflating criminal and tort (civil) law is also frequently done. You can be sued for basically anything. Illegality (breaking a criminal statute) is another level of conduct entirely.

Do I advise ignoring ratings? No. Has anyone, anywhere, at any time, been arrested or given a citation for towing a trailer with one gear ratio when another gear was specified by the manufacturer for that gross combination? Not to the best of my knowledge. But I’m open to hearing about it.
 

engineering

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This comes up often in some RV forums. I have yet to see a statute cited that restricts GCW for private vehicles. GVW yes.

Conflating criminal and tort (civil) law is also frequently done. You can be sued for basically anything. Illegality (breaking a criminal statute) is another level of conduct entirely.

Do I advise ignoring ratings? No. Has anyone, anywhere, at any time, been arrested or given a citation for towing a trailer with one gear ratio when another gear was specified by the manufacturer for that gross combination? Not to the best of my knowledge. But I’m open to hearing about it.

I kinda doubt criminality is much of a factor - but when a lawyer accuses you of negligence that is really really bad if there is an injury or death in the case.

A situation that is totally not your fault can become your fault pretty quick. If your trailer is 2,000lbs over the 'book rating' - it could be rather difficult to argue "but I changed the gear ratio......"

Is it worth worrying about? That is not up to me, but it is something I personally consider.
 

TheBaseModelGuy

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I kinda doubt criminality is much of a factor - but when a lawyer accuses you of negligence that is really really bad if there is an injury or death in the case.

A situation that is totally not your fault can become your fault pretty quick. If your trailer is 2,000lbs over the 'book rating' - it could be rather difficult to argue "but I changed the gear ratio......"

Is it worth worrying about? That is not up to me, but it is something I personally consider.


Checked my cars stickers at the door, nothing about GCW on it. Anyone know if its in a different location?
 

Octane

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Hi People,

I don't mean to hijack a thread but i am in the market for a camper and just cant deal with the 4450 towing capacity on my 3.21 ratio truck, people on this thread seem to know about the subject. My question is: is upgrading the differential the only thing needed to increase the towing capacity of my 2020 v6 ram to 7000lbs?

again sorry for hijacking but I'm new to this forum and forums in general so I wasn't able to find an existing thread
The main reason your towing capacity is lower is that v6 engine.If it had a v8 the tow cap. would be higher as you may know.Going to a lower axle ratio only makes it pull it easier but it is still going to be a lot on that v6. Go to anything up to a 410 will pull better.
 

TheBaseModelGuy

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The main reason your towing capacity is lower is that v6 engine.If it had a v8 the tow cap. would be higher as you may know.Going to a lower axle ratio only makes it pull it easier but it is still going to be a lot on that v6. Go to anything up to a 410 will pull better.
I haven't looked into 4.10 too much because I've seen that a good ratio for people who tow quite often, if I tow it will be max 3 times per year. I was also considering the 3.55 because I want to stay at least somewhere near a "Stock V6 Ram" I know the V6 can be special ordered in 3.55 ratio.

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engineering

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The main reason your towing capacity is lower is that v6 engine.If it had a v8 the tow cap. would be higher as you may know.Going to a lower axle ratio only makes it pull it easier but it is still going to be a lot on that v6. Go to anything up to a 410 will pull better.

Not really - the 8 speed transmission ensures the wheel torque required will be delivered. Moving to a 4.10 rear - simply shifts you up one gear. You are still at some ungodly RPM trying to pull a trailer up hills or travel trailers with a huge coefficient of drag. The engine torque is only about 270ft/lbs which is rather weak for most towing. The lower gears help you get going in first gear, but that is about it. It does, take the torque load off the transmission, but at the expense of higher RPM. Gears are definitely good for low speed use - bogging through mud, pulling out tree stumps, etc. Towing with the Pentastar V6 at regular highway speeds is a different thing. You are trying to just maintain speed when you encounter a hill. It really does not do well in my real world experience with a 4500lb 22ft Micro Minnnie. It spends a LOT of time at high RPM trying to make use of the peak torque that happens a little over 4k RPM.

I have poured over the math and lived the practical reality - in the end, I am putting a supercharger on my V6 for pulling because I need the extra 100ft/lbs of torque.

https://www.ramforum.com/threads/2015-pentastar-v6-towing.171807/page-6#post-2438098

You can do some visual work with how gear changes will impact your total ratio to the ground. The 8 speed trans is already so good at getting the engine to its sweet spot - gears don't help highway driving.

https://www.blocklayer.com/rpm-gear.aspx
 
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