I'm really dissapointed with the new 2005 48re trans. Unlike the 2004s the tow mode on the 2005s DO NOT lock out 4th gear. The 2005s shift into overdrive any time theres no load on third , regardless if its in tow mode or not. This means your going to have a gear hunter in the hills and mountains. You can however lock it in second if your running that slow.
I talked to the trans man at my local Dodge dealer about this , he insisted you could lock out 4th. So to prove this to me he brought it up on his computer, and his computer said on the 2005s you COULD lock out 4th when you pushed tow mode on. Well I said the computer is wrong or I 'm doing something wrong, because I'v drove three 2005s and activating tow mode didnt lock out 4th on any of them. So the good man took his scanner and hooked it up to a 2005 and sure as shooting to his surprise you could NOT lock out 4th no matter what. So he stated he was going to contact STAR and check this out. I dont know what Star is but they must have some connection here. I sugested that seeing as this stuff is computer controlled, maybe a simple computer reflash could get this feature back?? After all the 2004.5 had it.
Lets have some comments on this.

 

Well I hope that there turns out to be a fix for this. My Dad just ordered a 2005 with the 48re to replace his current (trouble-free) 2000 V-10 Ram with the 47re. He has been used to how that performed when towing their 9000lb. 5er. The folks are planning another trip from VA to CA and up through the Rockies again next year, which is one of the reasons for the new truck. My 5er is identical to his except about 800-1000lbs heavier becuase of the double slides. My 99 with the mods is about the same HP and TQ ratings as the new trucks and I don't think I would care for the 05 tranny and not being able to completely lock-out OD.
This is the first I had read of this change and I hope I haven't steered Dad wrong in his decision.

 

He better keep the V 10. I'v backed away from a 2005 just for this reason. My trans man called this Star Co and asked about it . Evidently Star is a support Co for DC on this trans. Star claimes this trans will sense the load and stay in the gear you need . But how does it sense the load,?? as long as truck is pulling it'll sense the load , but as soon as you back off throttle a little in third you loose the load and she'll shift to 4th. And if more hill is comeing right up again that it cant pull in 4th back into 3rd she goes. I call that gear hunting and I'm not going to let them tell me it'll work. for $40,000.00 . If you and your dad are pulling these 5rs around the U S you know exactly what i'm refering too.
If you got a grade thats 5-10 mi long it never a steady up grade . Theres little level spots and turnes going up. You can pull most of these in 3rd. at say 50 mph.
But if you hit a level for 300 ft and you let up throttle to maintain the 50 mph shes going to upshift because truck can now pull this in 4th at 50 mph. as soon as you hit the grade again and 4th cant pull it ,back into 3rd she goes. And it isnt just hunting between 3rd and 4th its in and out of torque connverter lockup in 3rd and 4th also. So the bottom line is its hunting between 4 different speed ratios here. NOT GOOD Really dumb, especially when they had such a good setup on the 2004.5

 

Neighbor just bought a 05.Already 8k plus on it.He's a horse hauler.Anyhow he says once you figure out how it works and get use to it he likes it a lot! Said it just took a little getting use to.Said as long as you keep a little pressure/foot on it will hold the gear until you back off etc.Said it works pretty good.

 

i like mine.

i tow in excess of 6000 lbs often. i can't complain about it. i use the tow/haul button until around 55 mph. i let the computer decide after that.


britt

 

Thats the problem, you cant always hold a little presure on it . slow for a short level spot ,or a curve climeing a mountain and you got a upshift. Then immediatly afterward you put the presure on and you got a downshift into 3rd again.. Thats gear hunting and thats whats ruining these torque converter lockup clutches!!!!!!!

 

Don't be too hard on the firefighter. He drives a manual trans, which is really the best choice for a diesel pickup truck. If your biggest decision with buying a new truck is the transmission, you should have bought an electronically controlled 5 speed (Allison or Torqshift).

Until one of the manufacturers makes an automatic trans that is designed to handle the torque (instead of adapting a higher speed capacity trans from a gas engine), the NV5600 is the one to get.

We need an automatic that can shift under full torque at about 1800rpm. Better yet a sequential manaul trans with steering wheel mounted buttons.

 

Well bluebb I don't really call that gear hunting.It sounds more like gear shifting.Hadn't seen any posts on torque convertor failure on the 48res unless bombed.With my 6 speed and towing heavy in mountains etc.I shift up a gear and then on the hill when needed I shift down a gear then crest the hill back up a gear.What you described is the same thing is it not?

 

if it doesnt detect strain by going into 4th gear, it will. If 4th gear isnt the best gear, it will stay in 3rd gear. These trucks have plenty of power to pull a 5000# trailer up mountains in 4th gear.

 

They pull a lot more then that in 4th gear.

 

Well guys Firefighter says he uses tow haul , (that dont sound like manual 6 speed to me ) Your right about the 6 speed manual being best for the job, but I want a auto.
Houndog, Your not getting the picture. If your pulling a grade at 50 mph in 4th of your manual trans and you hit a level spot for 200 ft and then grade continues, you would back off throttle to maintain the 50mph and then get on it again to continue clime. And if you did upshift to fifth and then downshift to 4th again you wouldnt let that clutch out with throttle on and make your clutch pull that engine down for engagement. You'd sync the rpm and throttle and torque together to make a good shift and then put the power to it. Without being able to lock out 4th in the auto is going to upshift as soon as you let off throttle at level area. and as soon as the grade starts again will go back into 3rd (UNDER LOAD WITH POWER ON) Now what happends on this downshift pulling this hill is the trans comes OUT of 4th gear torque converter lockup first, then shifts into 3rd, then goes (BACK INTO 3rd GEAR LOCKUP PULLING THE ENGINE SPEED DOWN FROM 3RD GEAR TO 3RD GEAR LOCKUP )with the torque converter lockup clutch with the power on. You dont shift a stick like this under power, if you did you'd burn up your clutch. You let up throttle , make the desired shift ,get the clutch out, then put the throttle to it . You cant let up the throttle to let this 2005 auto get into 3rd lockup as you start up this grade or it'll just go back into 4th , So you gotta hold the throttle on enough to make trans downshift, which INCLUDES the upshift from 3rd to 3rd lockup which is happening under power, thus burning the torque converter clutch.
This is the vary reason so many autos go to pot early, people just dont understand this torque coverter action and force there trans to LOCKUP under power ,takeing out the torque conv. clutch and then the disintigrating clutch contaminates the rest of trans causing complete trans.failure. When the trans goes into high gear one should let up power and let the converter clutch lockup. You cant do this with a 3rd gear shift if you cant lock out 4th.
The bottom line solution to all this torque converter clutch problem is to buy a good aftermarket torque converter . For instance we got 34 square inches of clutch surface on the 48re , you buy a ATS torque converter and put in there and you will have 117 square inches of surface. But why should we have to revamp a brand new truck? There pricy too. I'm not trying to sell ATS .I'm trying to tell you you need to be able to controll the gear selectoin in any auto. under sertain conditions. Dodge had it with the 48re in 2004.5 and they droped the 4th gear lockout in 2005. Ford and the GM allison you can lock out overdrive. These are 5 speeds, the cummins works quit well with a 4 speed , but this no 4th lockout is not good.

 

Would you believe even with the Hemi and the 545RFE 5spd auto behind it, it shifts into 4th (.75) O/D in tow haul mode. 5th is .67 O/D. Like the Hemi needs to be in either O/D towing at 1800rpm. It'll do it if the road is flat and no headwind but I'd just as soon run 2600rpm in direct. I ran 2500rpm all day every day with my '98 Cummins powered 5spd 4.10 at 70mph towing or not. Never hurt a thing. After three good Cummins powered Rams and then the '03 vibrator, I'm coming to the conlusion that another standard tranny will be in my next Dodge Cummins Ram. Had I known that even the Hemi powered Ram would be programmed to shift to O/D in tow/haul mode, I would have searched for a 5spd standard. The more I drive this truck the more I feel the 545RFE should be the one beefed up for the Cummins and the 47RE with the old program would be better suited for the Hemi. But what do I know... I only own and drive them in towing and empty situations. It takes and engineer with a degree in mechanical engineering who likely drives a Prius to decided how our trucks should be programmed. Hopefully some aftermarket pickup truck performance company will cough up a programmable TCM for our trucks so we can tailor the shift points and O/D to our liking.

 

I thought the TC locked up at 45MPH regardless of what gear you were in. So if the trans was to down shift from 4th to 3rd as long as you are going over 45 the TC would remaind locked. perphaps I am missing something here. As long as the TC stays locked than the trans is simply doing what a guy driving a manual would do shift into the nessary gear for the situation. Please corret me if I am wrong about the TC staying in lock-up.

 

TC unlocks to shift on any I've driven or owned. Then it locks back up after the shift. You can really tell it with a heavy load back there.

 

Thats correct Hannibal, To my knowlege the torque connverters unlock to make a shift . They got to ,if they didnt it'd be like shifting a stick without useing the clutch. Also the lockup takes place at different speeds for different gears. If the converters didnt unlock it'll stall the motor when brought to a stop.
I didnt realise that they have no gear lockout on there gassers eather? Man you got a double overdrive in a tow truck with the 360 hemi gasser and you CANT lock that into any of the desired gears??? That is worse then what there doing with the Cummins. The diesel will at least lug better. But you need rpm to pull with a gasser.
Thats makeing me think that when and if they ever put a 5 speed auto in the cummins they'll have no lockout and then she can hunt through 3 gears instead of 2. What a joke.