I’ve got a theoretical question to throw out there about the durability of the 47RE automatic tranny. Is it really that flawed a design as some make it out to be?? … or could it be that many owners are just plain demanding much more than it’s designed for and blame it on the transmission?

Let’s face it the 5.9 Cummins is a horse. It’s used widely in a number of medium weight commercial trucks/busses. Now, Dodge puts it in a light duty pickup to everyone’s delight ;D and … “Whoopee!” … “Wow!” … “My Stars!” … Arrrrgggghhh #%@* … heck, it’s the bloody transmission’s fault. It’s flawed? I don’t buy it. Hey, tell me if I’m wrong.

I’ve only 21K on my truck to date (just out of the womb, I know), with about 25% of the mileage towing my fiver. The tranny’s performing terrific. But, I’m driving it with what I call “mature discipline”. Don’t get your feathers up now, I don’t have anything against others that want to push it to the limit and beyond - done safely and sanely it’s harmless fun. It just seems from my time here on DTR that a lot of time has been spent questioning the durability of the 47RE behind the big 5.9. When, really doesn’t it largely come down to the gravity of the foot atop the go pedal?

 

don't know about behind a Diesel but the auto tranny behind out 95 1 ton flat bed gasser 4x4 has done really wel for us. it has just under 60k on it but the reason for the low miles is that it tows our Grave diggind trailer with a 770 JD loader/backhoe and all the attachments on a 25' GN trailer. in fact the truck is only unhooked to put new tires on it or for the new mufflers we just put on it last week.
I also have a 93 with almost 200k on the stock auto but its not a 47re :
DM01

 

i also second the driving habits as keeping a trans. intact..i beleive "helping" a trans. shift ( letting up on the throttle during shifts and especially TQ lock-up )..is a big contribution to it's life. I also personally "ease" into the throttle when I get on it, more so mid-range versus really bombing off the line I try to avoid. I also never fuel hard at low rpm's unless really necessary...I am however going to re-do my trans. only because the TQ bothers me in that it wastes so much power under 2k rpm's. My trans. performs perfectly with a pretty aggressive fueling box and some other small mods though, partly I beleive because of my driving habits....just my .002

 

My dads auto v-10 has over 100,000 miles on it with no tranny problems. The v-10 isnt exactly the cummins but it is powerful enough to test the auto and it hasnt exactly had an easy life, the mustangs aroung here can vouch for that .

 

I had 140,000 fairly hard, but not abusive miles on mine and it was still ok as long as I didn't do anything stupid. I am positive from friends in the tranny business that the dodge tranny is no worse than the Ford.

 

I think that Dodge had their share in simply bad 47s- and combined an engine with very much low end torque with a tranny suited for high rev operations. Add this to the fact that lots of the CTDs are used for towing or hauling, and to the sometimes bad service the trannies get and they will fail. How many drivers did never read the owners manual? Overfilled or starved trannies, wrong juice etc?
Personally I think that the stock tranny is not too bad, and will usually live a decent life if handled correctly. But an aftermarket tranny will make you smile because it will compliment the Cummins torque characteristics.

AlpineRAM

 

basicly a torqflite ,,,what can you expect????

 

I also drove my truck with a very light foot, which is probably part of the downfall of my tranny. Not enough line pressure to keep the TC from slipping while towing.

I asked the tech that did the work on mine about the 47RE and he said it's not a bad tranny, just lousy parts inside of it. With my upgraded tranny it is a whole different truck! ;D

 

Ditto on the junk parts inside. The two biggest problems with this tranny are the VB and converter. Secondly are the clutch pack seals and bands. I know I snapped one. :'( Ouch. Fix these and you'll be happy for a long time. ;D

 

I don't think it is the tranny it self.
Mine started shuddering around 40,000 miles and I changed the torque convertor and valve body and that did the trick.
I have over 104000 on it now.
I was always told this tranny was build for gassers not diesels,it may not be true,but all I can say ever since the TC and VB change it has been flawless..Thanks DTT

 

I have to agree with the opinion that the tranny is too weak or poor build quality. My truck had the trans go out at 41,000 miles and it had never had a hitch stuck in the receiver or a big load in the bed. I also have a pretty light foot, (my highschool burnout days are long gone). I enjoy the ease of driving the auto in traffic, but if I had it to do over again, it would be HO 6 speed for me. Just my opinion, I hope this rebuild lasts for another 100,000.

 

I have over 135,000 on my stock tranny. I have used the truck for everything from plowing to pulling, to hauling camper on the beach.

Just started adding HP last week, (HX35 / 40 turbo, TST box, Scotty II, DDII's) and have no problems running the box on power level 5. I have to be running at least 40mph before putting the right pedal on the floor otherwise the tranny will slip.

Having the DTT stuff done next week...

So overall, I would have to say that my tranny has held up very well for what I have used the truck for.

My previous ford lasted nowhere near this long.

JB

 

Getting the trans to hold power is not hard. With only minimal mods these trans are holding 2,000HP in gasser drag racers. There is a big difference between a gasser, and a diesel. RPM

A gasser might make 2,000HP and 1,500Ft/Lb at 8,000RPM. At that RPM there is more than enough pump speed to keep trans pressures up.

A diesel will make 500HP, and 1,000Ft/Lb at 2,500RPM. Something a gasser will never see.

A stock truck will make 400+Ft/Lbs at 1,600RPM That's torture on a transmission. No wonder they fail, not enough pump speed, and torturing the trans fluid with an inefficient torque converter.

Low Trans Pressure, High trans temperatures, leaky internal seals.
Great combo for a trans that will :P on you.

It's a good tranny. Just needs some aftermarket work.

Merrick Cummings Jr

 

I second MCummings notion.
An AT is killed by torque. Torque makes clutches slip. Clutches need apply pressure to hold torque. Apply pressure is made by a pump and fed through a throttle valve. This pump needs to turn and the throttle valve needs to be open to have much apply pressure. So feathering the accelerator and lugging the engine and trans around will kill transmissions. Internal leaks will kill them too. I think that most of the complaints about defect trannies come from people who say that they never towed and always feathered the throttle, made the trans go into OD lockup as soon as possible before puttingthe coals on. It's exactly this behaviour that makes the trannies die. Throttle valve cables that are adjusted loose to make for comfortable sloggy and early upshifts do contribute too.
Aftermarket VBs do take care of a part of this problem. But usually people use the aftermarket VBs when they feel that the stock tranny slips. so since there is something wrong in there, usually not the VB, this addition can often be masking the problems that really are in there. Seals that had leaked before do now leak under higher pressure and the holes in the gaskets are getting wider. (erosion)

Just my 2c

AlpineRAM