1500-2500 question

Currently I have a 2011 5.7 ram. It has the lifter tic and will be a 2k fix.. or more. I hual a 38ft flat bed bumper pull trailer a lot with (2) 2500lb cars on it. From FL to South Carolina and Georgia a lot on the weekends for racing. I test drove a 6.4 3500 and loved it, but it was single cab and couldn't do it.. does the 5.7 2500 have the same exact motor as the 1500. If not does anyone know the upgrades it has? Just didn't want to spend a lot more money for the same truck pretty much.. also how much better is the transmission in the 2500 vs the 1500? Just trying to get the technical differences in them. My 1500 pulls the trailer fine but I know it's just not good for it. Thanks for any input!

Actually, the 1500 5.7L makes 395/410 HP/Torque, the 2500 5.7L is rated at 383/400 HP/Torque.

Gearing and spring rates/payload in the 2500 is different, hence the payload and towing capacity values being higher.

The 1500 transmission is the ZF 8HP70 8-spd auto licensed by FCA from ZF vs. the 66RFE 6-spd auto in the 2500 with the 5.7L, a 68RFE is found in the 6.4L trucks.

The RFE transmissions are designed and built to haul the loads a 2500 or 3500 is rated at.

If you can find a 2500 with the 6.4L engine/68RFE transmission in the cab configuration you want it will be the tow vehicle you are looking for.

Good luck.

I can't lay out specifics for you, but I can give you a few ideas from what I have gleened.

Transmissions- totally different ball game. The 66rfe on the back of the 5.7 and 6.4 in the HD trucks is nothing like the lighter duty trans. Shifts are intentional by design. The 66rfe if I understand correctly will lock the torque converter quickly in all forward gears other than 1st. This results in a more pronounced shift- to me at least. They are definitely a trans meant for heavier work.

The 5.7 in the 2500 has different tuning for sure. The HP/TQ is a little lower than it's little brother 1500. It is designed to run like a workhorse all day long for years though which is likely why. It lacks MDS and I suspect it has a different intake and maybe some other pieces on the top end to make a more grunty torque curve. I am also suspect that the oil and cooling system is a bit heavier service, but I may be wrong. I have no evidence to support the theory of a modified top end other than the dozens of old small blocks I've rebuilt in our farm trucks.

For a direct truck to truck power comparison, my 2500 with the 6.4 3.73 pulls no harder than my 1500 with the 5.7 3.92 once on the highway. However from a stand still I have way more grunt with the 2500. I know you're looking at the 5.7, I am just illustrating that in the pulling power area, you will likely see no difference other than the one made by the 6 speed- which is significant I suspect.

To be honest I think you'd be ok with the 5.7- but I think you'd be happier with the 6.4. I went for the 6.4 for the added GVWR (10k vs 9k) and the MDS plus the 6.4 comes on to torque at about 1000rpms less. I still feel the 5.7 is a stout little mill though and would certainly serve you well. I see some great big damn campers and cattle trailers behind a 5.7L and they always make it home.

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MADDOG said:

If you can find a 2500 with the 6.4L engine/68RFE transmission in the cab configuration you want it will be the tow vehicle you are looking for.

Good luck.

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I don't think the 68rfe can be had on a gasser, can it?

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Thanks, those are very good replies exactly what I was looking for! Goal is the 6.4 hemi but I'm on a budget and a lot of the trucks I find are the 5.7 2500's and wanted to know if it's worth it. Any 2500 is a purpose built truck to tow so I should be in good shape. Thanks guys!

Traded a 5.7 for 6.4 in a 2500. Can tell a difference in low and torque and a large difference in MPG. 6.4 drinks it. There is no deal breaker performance difference between the two, the 5.7 is highly capable as its been used for years in the HD.

DBrown21 said:

Thanks, those are very good replies exactly what I was looking for! Goal is the 6.4 hemi but I'm on a budget and a lot of the trucks I find are the 5.7 2500's and wanted to know if it's worth it. Any 2500 is a purpose built truck to tow so I should be in good shape. Thanks guys!

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The 6.4 is a better built motor for HD work. Doesn't mean the 5.7 won't survive but it's not simply a matter of displacement. FYI, all gasser models come with the 66RFE, 68RFE is only used in the Cummins models.

6.4 liter Hemi truck engines for Ram pickups and chassis cabs

smurfs_of_war said:

I don't think the 68rfe can be had on a gasser, can it?

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I think the 1500 6 speed is the 65RFE and the 2500 atleast the 6.4, has the 66RFE.

for the OP, if you tow your set up ALOT, you'll definitely be happier with the 2500.

I routinely tow 8000 lb loaded trailer. Did it with a 2014 5.7 1500 with the 6 speed and 3.55 gears. Some get very offended on this forum when I say this but the 6 speed on the 1500 is aweful. I haven't driven the 8 speed so can't comment on that. Having said that, the 1500 did fine with the trailer with the occasional tail wagging the dog feeling.

I since traded up to a 2015 2500 6.4 with 4.10 gears. significantly less white knuckle events and just more comfortable towing the 8000 lbs. The 6 speed on the 2500 is better than the 1500, not perfect, but better. As for the get up and go, smurf_of_war summed it up. Both trucks pulled fine, of course, the 1500 was pulling almost 2000 lbs less in chassis.

I know the 5.7 HD from test drive only, never pulled with it.

If you need a new truck and budget doesn't allow for a 6.4, considering the 5.7 did HD duty before the 6.4 was available, I think you'll be fine. But if you have the luxury and want to stay with gassers, go for the 6.4.

smurfs_of_war said:

I don't think the 68rfe can be had on a gasser, can it?

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You are correct. I read the line below in the spec card which is the 6.7L CTD line.

smurfs_of_war said:

I don't think the 68rfe can be had on a gasser, can it?

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Yes and no. Basically no but they have the exact same ratios so they are kind of the same thing.

fwiw the tranny in the 6.4 SUCKS! It's by far the worst part of an otherwise great truck. The 1-2 gap is ridiculously large (because the ratios were intended for a diesel). Mine blew completely @ 38K miles and was rebuilt under warranty. It feels like it's going to blow again any day and I almost hope it does.

So, my complaints are two fold - performance and reliability. I realize I'm in the vast minority with a failure on the reliability thing but the performance sucks either way.

mtofell said:

I realize I'm in the vast minority with a failure on the reliability thing but the performance sucks either way.

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I don't want to make it seem like a trend, but the tranny in my '14 6.4 2500 blew too. Bits and pieces all over the inside at about 52000kms. Right around when yours did. That's why I am in a '15 now with a severely lighter wallet. No way in hell I was dealing with a rebuild.

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Mtofell how much towing did you do before your transmission died?

Iron Outlaw said:

Mtofell how much towing did you do before your transmission died?

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Not much at all - maybe 5% of the miles up to that point. Also, my truck is totally stock and I really drive pretty conservative. It actually blew under very low stress circumstances. I was in stop/go traffic on the freeway rolling along at around 5-10 MPH. When traffic cleared and I hit the gas to accelerate the tach went up and I virtually stayed still. I was able to limp about a mile to the next exit.

The tech said the throttle body (I think that was the part) totally ruptured. I wasn't happy about just getting a rebuild and I'm pretty sure there's still something wrong with it. It has a terrible downshift from 2-1 while engine braking and intermittently shudders at that same shift point when rolling into a hill around a corner at a certain speed.

I've been to the dealer and they claim a combination of it's normal and they can't make it do the shudder and harsh downshift that I can. I'm basically just frustrated with my dealer and don't have time to screw with it right now. I have the Lifetime Maxcare warranty and am just kind of waiting to see what happens. I should probably just trade it in but I have air bags and a 5th wheel hitch that I'd want to take off and the whole process is just a PITA.