Towing with 3500 srw cc 4x4 long box 3.42

[jaymxr]

Im looking for some advice from those of you that tow a fith wheel with a newer ram 3500 cc 4x4 long bed 6.7 and Aisin tanny. I was stuck on a 3500 dually with 410 or 373 but now back at the draw board to look at other options. Like feel milage i will get with the 342 vs 373 and 410. So looking to get some option on this should i stick to the dually or go with the SRW. I tow a 07 Montana. What are the positive and negative that you found and if you could do it again what would you change. Thank you

[hankpage]

The 3.42 ratio will only improve your solo or possibly your flat-land towing. The lower rears will be much better for towing especially where steeper grades and frequent start and stop are involved. SRW with adequate payload will be cheaper to maintain and a more city friendly daily driver. DRW will add safety and stability while towing but may have parking restrictions in some locations. The choice is a personal one based on YOUR needs and how you use YOUR truck. JM2¢, Hank ( My last truck had 3.54 rear and gave great fuel mileage solo but suffered when towing. I choose the 3.73 on my present truck and have been happy with the compromise.)

[LittleJoe]

How heavy is your trailer??

Do you tow mountains often?

You can only get the Aisin in 3500 and only 3.42 in SRW.(a bad mistake not to offer other ratios IMO).

The 3.42 is rated too tow quite heavy, but 3.73 is a better allround gear in heavy towing etc.

The tall 6th gear OD is very tall with 3.42 which often would mean you lock out 6th and tow in 5th.

Unless you often run 80mph empty, the 3.42 is not that attractive for towing

[65aircooled]

If you haven't yet, check out the Cummins Forum and ask the same question there. It seems that most Aisin/3:42 owners complain of the lack of giddy up when towing. As said above, depends on where you tow and how much towing you'll be doing.
I had an older CTD with 4:10's towed great but MPG's sucked when not towing. I guess you need to compromise one way or another

[bsmith0404]

If you haven't yet, check out the Cummins Forum and ask the same question there. It seems that most Aisin/3:42 owners complain of the lack of giddy up when towing. As said above, depends on where you tow and how much towing you'll be doing.
I had an older CTD with 4:10's towed great but MPG's sucked when not towing. I guess you need to compromise one way or another

I don't have a Dodge, but a friend (well acquaintance) of mine has the Aisin with 3:42 and that was his exact complaint. He says it as gear hunting, but realistically it's just short on power for that tall gear. He'd probably be fine if he chipped it, but if you don't want to do that the 3:73 seems to be a happy medium.

My opinion of SRW or DRW. I never wanted a dually, bought one because of the trailer we wanted. Now I love it! I still think SRW are better looking/driving trucks, but won't own another one unless I downsize the camper. The stability and load on the tires is my reasoning. I don't need a blowout on a SRW at 60 mph with 15k lbs pushing me. That would be bad with 11k lbs as well, but risk is reduced since the tires on a SRW would not be stressed as much on a lighter camper, unless it is extremely pin heavy.

[340_Formula_S]

I have the 4.10's in my truck. Unless you are working the truck for heavy purposes or do a lot of camping, with a fair size camper in the hills, you most likely do not need them. On the other hand, the fuel mileage on mine is about 16.5 avg on the highway and 11 avg towing, uphill, downhill and you will forget that you are loaded. The other advantage to the 4.10's is that they work the exhaust brake better. It is a great gear if you have a need for it, otherwise, go with a 3.73.

[Javi]

I don't know poop from shinola but.... I do tow a 12.3K 5th wheel with a diesel and 3:31 gears.. With the new style 6+ speed automatic transmissions getting off the line isn't a problem. However, if I had to do it over again (and it may happen yet) I'd have nothing less than 3:55 and I am leaning toward the 3:73's for gearing.. Even with our reasonably flat roads it will hunt gears between 5th and sixth at 60-63 mph.. they just don't like the rpm to drop below 1600 with that weight.. To that point I'm finding myself locking out 6th most of the time, unless the road is really flat.

I'm probably going to install a set of 3:73's this summer..

[Barbell]

This doesn't directly answer your question because we tow with an older CTD; '01. However, I think the 3:73 ratio is best balance. We have pulled a 36 foot fiver from coast to coast several times with no problems while averaging 11-13 mpg and 20+ while empty. When this truck is replaced, it probably will be a 3500 SRW. The main reason is that a dually longbed with crew cab is too long and wide to fit into a lot of parking spaces, especially in the East. We have enough problems fitting into spaces with this old truck. We are in Charleston, SC now and this truck won't fit into some parking garages and street parking is a challenge.

[Desert185]

With older rigs having smaller diameter tires, the 3.55 gears work pretty well. The newer rigs have larger wheels and bigger diameter tires, so something in the neighborhood of 3.73 gears would be a better choice for a rig that not only tows, but is also a daily driver.

This engine RPM calculator might help with the decision process.

http://www.csgnetwork.com/multirpmcalc.html

[gearhead]

First, I would be absolutely positively sure that the SRW had the payload capacity for your trailer or any other one you may want. I'm running 3.55 with 20" tires on the Ford. Tows well on the flat and low hills. I haven't got to the mountains yet. I'm not expecting issues other than maybe locking out 6th gear. I get 17-18mpg at 70-80mph empty, and 11-13 towing on flat and small hills at 65-70mph.
I lean towards SRW because I'm getting too old and lazy to hand wash a dually. The SRW runs through an automatic carwash just fine. But I will say I'm getting closer to payload capacity (3265#) than I ever thought I would.

[65aircooled]

OP, do keep in mind that Ram only offers the 3500 SRW Aisin with 3:42 gears. If you want 3:73 or 4:10 you have to either get a DRW or re gear which in my opinion is not worth doing aftermarket. Best of luck with your decision, mine is not Asin equipped but I love it, the manual transmission/3:73 tows great. Would not change it for the world:p

[christopherglenn]

I wouldn't regear, the cost and likely powertrain warranty issues as well as the ABS being mad, it isn't worth it on a new truck. If your weights need the dually, get it and the 3.73, if not the SRW will net better empty mpg's. I got my dually 4 years before my 5er, with a TT in between. Having to much truck isn't an issue, especially if you may upgrade within the lifetime of the TV.

[gtsum2]

The op. I get 21-22mpg hwy and about 17 city empty. I do kind if wish it had 3.73 as it can lug around at times but ram srw only comes with 3.42