Levi_plummer
New member
Thank you sir! I am hoping this will hold some small injectors and an he351 or hx40.
My 47RH Build
- Thread starter Ghostman
- Start date
Big Blue24
Comp Diesel Sponsor
The stock 5 pinion steel overdrive planetary is adequate for most builds and does not need to be upgraded if it's in good shape, I've only seen (1) bad one in about 20 core transmissions.
The first planet on the intermediate shaft, also called the forward planet, is aluminum and (5) pinion on stock 47rh transmissions. For 500 HP/1000 ft-lbs or less, the aluminum planetary will hold up just fine. I actually put 1476 ft-lbs through the aluminum planet in the 47rh on my Junker Drag Truck. It is now going to be upgraded to a used stock 5 pinion steel planet from a 47re (direct swap, just needs the cheap $3 plastic sleeve installed with the steel planet).
The aluminum rear planetary with cogs that fit into the reverse drum do not need to be upgraded till well over 700 HP/1500 ft-lb. There are several aftermarket options available for 5 of 6 pinion aluminum, I've never seen a stock aluminum 4 pinion rear planet break from torque, just destroyed from worn out thrust washers/bushings which could be prevented with custom machined/added torrington bearings.
For what it's worth, the 48re came with a steel rear planet so apparently Dodge/Chrysler decided it was a worthwhile upgrade. I personally won't upgrade my 47rh/re's until I see an aluminum rear planet failure from torque overload.
The first planet on the intermediate shaft, also called the forward planet, is aluminum and (5) pinion on stock 47rh transmissions. For 500 HP/1000 ft-lbs or less, the aluminum planetary will hold up just fine. I actually put 1476 ft-lbs through the aluminum planet in the 47rh on my Junker Drag Truck. It is now going to be upgraded to a used stock 5 pinion steel planet from a 47re (direct swap, just needs the cheap $3 plastic sleeve installed with the steel planet).
The aluminum rear planetary with cogs that fit into the reverse drum do not need to be upgraded till well over 700 HP/1500 ft-lb. There are several aftermarket options available for 5 of 6 pinion aluminum, I've never seen a stock aluminum 4 pinion rear planet break from torque, just destroyed from worn out thrust washers/bushings which could be prevented with custom machined/added torrington bearings.
For what it's worth, the 48re came with a steel rear planet so apparently Dodge/Chrysler decided it was a worthwhile upgrade. I personally won't upgrade my 47rh/re's until I see an aluminum rear planet failure from torque overload.
Ghostman
24v crazy
Good information, my only concern with the planets in mine currently is the amount of lateral slack in the gears and the wear from the thrust washer. I'm not sure how much slack is acceptable, but it seems too much to me.
12vCumminsFTW
Active member
I believe the Part# for the bearings is D36235CA.
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Chrisd91
New member
I believe the Part# for the bearings is D36235CA.
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That is sweet, if we could have specs on how it was machined that would be awesome
akadiesel
Diesel by birth
12vCumminsFTW ,just curious to your application? I was talked out of doing this several years ago by one who did tests and only gained 1.5 tenths of a second in a 727 muscle car. Plus the concerns over the extra lube needed for torringtons to survive in a DD. I definitely hope it works well and if not, maybe we can add some lube there. I think it may be overkill, but That is what we do!!!! For the most part, I agree with BigBlue. Aluminum is almost as good as the powdered metal steel. Almost! Failure is almost always the splines. More gears equals more drag. I've not looked lately, so maybe someone is making a billet planet set for a 518?? SMR http://smrtrans.tripod.com/smrtransmissionsintro/id17.html does for a 727, which can be made to work and a bolt in sprag for a 518. If on a budget,drill and tap your own sprag. For those that don't know, a spun sprag is why you buy a scatter shield!!
Headcase98002
New member
Get a hold of Lavon, he seem to have a good price on them.
Chrisd91
New member
Ghostman
24v crazy
Going through this valve body tonight putting in the shift kit and noticed that the PO had already done a few mods. I noticed this one here. Looks like he stuck a BB in here. I'm guessing this is a way to get more lock up pressure? Should I leave it in or take it out?
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