OSA Garage- Transmission advice

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HiredHand

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Has anybody had a 47RH behind a 5.9 Cummins rebuilt? If so who did you use to rebuild it and what upgrades did you make. Yes, I've been reading several Cummins/Dodge forums but I'm hoping to hear what the locals have to say.
 

4play

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There are many upgrades you could do and the level of upgrades is dependant on what you want to do with it and how much money you have. Its fairly easy to get a 12v to around 350-400HP and 800-1000lb-ft torque. These transmissions had problems with stock power levels so I would consider some basic stuff. I would at least consider an upgraded valve body, or valve body mods/shift kit, torque convertor at least a single disk billet convertor (custom stall optional), upgraded clutches/bands and servo's and servo levers. You can find upgraded parts within factory apps too. 47RE and mostly 48RE parts are interchangeable the 48RE has a few goodies for the 47's. As long as its not for some type of racing, abuse or pull truck, I dont think you need to go crazy with the alloy shafts and custom hard parts though. I would think the T/C might be the biggest money chunk on parts.

There are also very reputable companies that specialize in diesel trans/perf and sell rebuild kits too. I would say if you are wanting a strong rebuild and are mostly stock, just call a local diesel perf shop and see who they recommend and call them. Most trans shops will probably be fairly familiar with 46/47/48 trans

Google companies like these, if not interested in their products you might at least gain some knowledge
Goerend Transmissions ( Dave Goerend ) he is an outstanding guy and very knowledgable on dodge trans apps.
DTT transmission, DTT is a big perf trans company
Suncoast, another big perf trans shop
BD
ATS
 

FullAuto

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I had the automatic behind my '06 5.9 Cummins rebuilt. I'm not sure which transmission it is. I received quotes from a few places and then got referred to a guy who does transmissions and rearends way out off Highway 9 past Thunderbird casino. He does them at a shop on his own property but it is his only business and he had a sign out front advertising his business. It's very "back woods" though. He bought it all the upgraded clutches, etc., provided the receipts, showed me all the stuff he pulled out of mine, R&R'd it from my truck and I had it back in 3 days. Looking at his place, I'd have NEVER used him had I not really trusted the guys that recommended him. He put a 2 year warranty on it. And it only cost me $1200 (including having the convertor rebuilt).
 

_CY_

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ran a 47RE on my 97 Cummins 12v for several years with zero issue. routinely yanked 25k+lb with my stock tranny. key to keeping your auto tranny alive is understanding why transmission die mated to a Cummins diesel.

a stock Cummins turbo diesel motor delivers max torque at about 1600 rpm. at that engine speed most transmissions are not spinning fast enough to produce max hydraulic pressures needed to survive loads Cummins is delivering.

under light loads, 47RE or other series auto transmission will usually not have issues. the problems starts when a serious load is applied. it's nothing for Cummins truck to yank 15k+ lbs. it'll do that and beg for more.

if you are running stock auto transmission under those type loads with a Cummins. try to keep your diesel over 2,000 rpm. it's very important NOT to accelerate when overdrive kicks in. ease off when overdrive is engaging, after overdrive is fully locked up, stomp on it.

Dave Goerends is the way to go when it's time for triple disc torque converter. then if your wallet is feeling fat and motor is putting 600+hp ... not unusual to spent $6k+ building an auto tranny that bullet proof.

best transmission survive a Cummins up to about 500hp is a manual 5sp. Since I was convinced that a Cummins 12v Turbo Diesel is the best truck on the road. And I didn't feel like spending $6k building up my auto tranny. I had to have a 5sp manual tranny.

looked into changing out 47RE to 5sp.... after I found out what a major PITA that job would be. Starting looking for a new truck.... took me 3 years to find it ... a 96 Dodge 2500 with 12v Cummins, extended cab, 5sp, 4x4 with 67k mile on the clock.

it's hard finding a super low mileage 12v Cummins 3/4 ton truck. for some reason Dodge decided 3/4 ton truck didn't need manual transmissions. something like a 25 to one ratio between auto to 5sp for 12v 3/4 ton truck. whereas it's easy to find 5sp on one ton 12v trucks.

my 96 12v is lightly bombed to about 400hp. upgraded to a single disc ceramic clutch good to about 500hp. my plans are not be go above 500hp, since I don't feel like building out my 5sp with billet parts and I don't want to break anything.

installing a clutch in a 4x4 Cummins is a major job.... mine was a PITA!!!
mine has a 5in exhaust system installed, which eats up precious space transmission needs when stabbing back in place. good thing I've got a pro transmission jack.

total cost for a new Sachs full ceramic disc clutch with throwout bearing and pilot bearing is about $350 from Orielllys. they've got to special order it. most will not know they've got access to ceramic clutches. if you order a Southbend or Valair ceramic clutch is about $650 and carries IMHO a poor warranty, very short. vs a lifetime warranty for a new Sachs Ceramic clutch

a brand new Sachs ceramic clutch (good to 500hp) from Oriellys is about half price and carry a lifetime warranty. I was told to delete this same information, when I posted it on the Cummins diesel forums.
 
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HiredHand

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Well, my motor is basically stock. The trans was rebuilt about 16,000 miles ago with some upgrades. So, imagine my delight when it slipped while towing around 10-11k pounds up a little hill. Unfortunately, I aquired the truck after the trans rebuild was done. I've also found out the the shop that did the rebuild might not have been doing the best work possible.

I've got to drain the fluid and see what's down in the pan. So, I might be jumping the gun here.
 

_CY_

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drain fluid, then adjust your clutch bands and replace with synthetic tranny fluid
hopefully that will take care of your problems.... instructions http://www.google.com/url?sa=t&sour...sg=AFQjCNE5fCryALRo8RntHmBMzGuN0n7ZNQ&cad=rja

there's several other things to do if you are a decent mechanic with tools. loads of help on the Cummins forums.

you need a factory workshop manual if you go very deep.
otherwise $$$ for a pro to take care of.

did you get a copy of receipt for transmission work? usually a reputable shop will take care of issue if they did the work and you have the receipts.

if there's no receipts, there's a possibility seller may have embellished the facts

Well, my motor is basically stock. The trans was rebuilt about 16,000 miles ago with some upgrades. So, imagine my delight when it slipped while towing around 10-11k pounds up a little hill. Unfortunately, I aquired the truck after the trans rebuild was done. I've also found out the the shop that did the rebuild might not have been doing the best work possible.

I've got to drain the fluid and see what's down in the pan. So, I might be jumping the gun here.
 
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HiredHand

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I've got a factory service manual for the truck. Running some pressure tests on the transmission is defintely on my to do list. I'm going to check out my TPS while I'm at it just for good measure.

I'm hoping the synthetic fluid and extra capacity that are in the transmission did their job.


drain fluid, then adjust your clutch bands and replace with synthetic tranny fluid
hopefully that will take care of your problems.... instructions http://www.google.com/url?sa=t&sour...sg=AFQjCNE5fCryALRo8RntHmBMzGuN0n7ZNQ&cad=rja

there's several other things to do if you are a competent mechanic with tools. loads of help on the Cummins forums.

you need a factory workshop manual if you go very deep.
otherwise $$$ for a pro to take care of.
 

_CY_

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don't worry about the pressure tests until clutch bands are adjusted first.
that's most common issue....

if torque converter was replaced 16k miles ago. unless you've been abusing tranny. it should be OK... unless you've got receipts, you really don't know what was done 16k miles ago.

I've got a factory service manual for the truck. Running some pressure tests on the transmission is defintely on my to do list. I'm going to check out my TPS while I'm at it just for good measure.

I'm hoping the synthetic fluid and extra capacity that are in the transmission did their job.
 
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4play

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Adjusting TP would only affect when the T/C locks up and when the O/D shift takes place. Band adjustment mainly affects shift timing as in how long it takes to complete the actual shift. If Bands are loose you would more than likely have a flare-up on shifts, but the checks and adjusments are easy to do. Keep in mind the bands only affect manual low-1st gear, Rev, 2nd, not "D" 1st, 3rd or O/D.

If you were having a slip towing in 3rd or O/D, I would assume its probably the Torque Convertor, but could be Direct clutches, or O/D clutches. If you manually locked out O/D on the shifter you will get T/C lock up in 3rd, so it could still be the T/C slipping in 3rd. Pressure checks could tell you something, and I would bet if the trans was built not too long ago, they either didnt know what they were dealing with, or didnt address much for upgrades. Simple valve body mods and a good Torque Convertor is probably all you need.
 

HiredHand

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4play, the transmission supposedly has a Transgo shiftkit installed. Under light throttle the transmission doesn't shift into OD until 48mph and locks up at 50mph. So, I've never had usable OD in around town driving. I always attributed that to the characteristics of the shift kit and its honestly something that's bugged me.

I had OD locked out while I was towing and was only doing 35mph or less while pulling the small hill up to my buddies house.

I appreciate all the input so far. You guys are helping reassure some of my suspicions. I think 4play has it right that the transmission wasn't set up correctly.
 

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