what are you towing with your 6.4 Hemi

I have a 2015 Ram 2500 Outdoorsman crew with the 6.4 HEMI and 4.10 gears. I tow a 29 ft TT that is quite tall and is almost flat in front. (Poor aero for sure) total weight of everything ready to camp is just under 19000 lbs. I have all the power I need to tow @ 65 mph in 5th for the most part. I have found I do not like the tow/haul mode as it seems to shift too late after losing too much speed then wants to slam down to 2nd or 3rd. If I shift myself prior to a hill climb then very rarely do I need 3 or 2 except on the steepest of hills. I'm just over 10000 km now and the motor seems to be loosening up and really coming alive. Downside is of course fuel mileage but it is actually slightly better than my 2005 ram 1500 with the 5.7 3.92. I do miss the 2005 because you could scream that engine and it didn't seem to have any torque management. You can really tell the computer is hold something back with the 6.4 which is I am guessing is the 66rfe transmission. Also yes the 1-2 shift sucks real bad when your accelerating up hill!.

Matt

I have over 250,000 miles delivering TTs with the 8 speed many of them going over the western grades. It's the diesel with 3.92s and a tune with about 480 foot pounds of torque. After my experience with this trans & also having seen the improvement this trans made with drive ability & mileage with a 5.7 I can't see why the 2500 with 6.4 isn't using this tranny. Granted my truck is probably 1,500 pounds lighter & I rarely have TT or loads over 8,000 pounds but the setup puts out and the trans holds up to more torque than a stock 6.4. Seems to me it would hold up and dramatically improve both drive ability & mileage.

On another note.. If I was buying something to tow 12k & more especially to travel over grades I would be getting one of the bigger diesels not any Gasser or a little diesel. Just my thoughts.

I've got a 2500 with the 6.4 and 3.73's. Pull a 26 ft toy hauler. Camper usually weights in about 6800lbs when I'm traveling. No issues. Happy with my decision on this truck.

Strange that the 4.10 is so difficult to find. I think it was included as part of the "Snow Chief" package which pretty much every HD truck has here in snow country has added... everyone wants a plow truck

I did a TON of homework on the 6.4 and read everything ib516 ever wrote about his...(thanks). IMO, it is a very capable engine and I was very close to buying one.
Ultimately, I couldn't find a 4:10 and didn't want to settle for the 3:73.
My lovely wife said "get which ever one will be the quietest"....:B

spoon059 wrote:
My friend tows a 30 +/- foot 5th wheel that weighs about 10K lbs with his 6.4 with 3.73 gears. He wanted the 4.10's but couldn't find any on the lot and didn't want to order one. He is annoyed with the way it shifts while towing up mountains. The trans wants to stay in 4th gear too long, then skips 3rd and goes into 2nd with high RPM's. He has figured out that he just needs to manually downshift into 3rd gear when approaching a climb.

Truck handles the weight just fine though, other than the transmission programming quirk.

A little off topic, but my Ford does the same thing... 4th to 2nd. Usually when I'm in cruise and don't think to turn it off before hitting a steep hill.

From all the reading I've done Ram really ought to change the ratios in the 66RFE because that seems to be the main sticking point with the gas Rams. Do GM and Ford use the same ratios in their gas and diesel HD trucks? The Cummins has no issues at all with that 1-2 gap.

2015 3500 with 4.10 gears pulling a 14k toy hauler in the wind and mountains of MT. lower elevation, rolling terrain it is quite a bit stronger than my '08 V10 except for 0 to 50 mph. In the steeper stuff the Ford would win every time. That first to second gap in the tranny and the computer nanny that limits power at lower speeds kills the performance at anything below about 45 mph. Really like the rig overall, would not buy another to pull heavy with.

What's wrong with using 2nd and high RPMs? It's a gas engine, turning RPMs is what its built for. Mine doesn't even have a redline on the tach. 5.7 had one, 7000 I think?

I don't try to out think the computer, I figure the guys in Auburn Hills with engineering degrees probably knew what they were doing when they programmed it.

Only time I manually shifted the 5.7 towing in the mountains was when I wanted to go really slow down a grade.

I used to tow a 2010 Cougar 5er. It had 3 slides and was 37' long. I have weighed it at the CAT Scales many times, and fully loaded for camping, it weighed in at 12k.