Max Power For a 48RE

[Driftwood Ram]

My son-in-law has a HO 2003. How much power are you guys running without smoking the stock transmission??? He is towing 13K.

Thanks

Tracy

 

[Matt400]

660 ft lbs here with no trouble yet.

 

[manganos]

Good question. I'm planning on some type of box and wondering how much I could go too without telling my wife I need a new trans or an upgrade. I'm trying to hide the fact I'm buying guages, AFE, and the box as it is!

 

[fencebuilders]

275/612 at the wheels,no problems so far.

 

[XcumminsX]

It all matters how you drive. Ive been told 400hp is the max for the stock components. Id say you have to be a light footed driver though.



Nick

 

[Snow man]

Around 400hp is the limit. Nick I disagree with you in that a lightfooted driver is the worst kind for either the 47 or 48REs. Especially a light footed driver with a fueling box turned up. Much better to drive it with your foot in it. Light footed guys tend to lug the truck too,another mistake. I drive my truck like i stole it,other than snapping the intermediate and 2 output shafts,(my own fault)my DTT modded trans has been great!

 

[Matt400]

Originally posted by Snow man

a lightfooted driver is the worst kind for either the 47 or 48REs. Especially a light footed driver with a fueling box turned up. Much better to drive it with your foot in it. Light footed guys tend to lug the truck too,another mistake.

That confuses me, how is it that putting less power to the trans is more hard on it? And why do the conservative drivers run their auto's for far more miles than the hot rodders?

 

[ChrisTucker]

an auto trans needs rpm's to keep the fluid/line pressure up thereby preventing component damage. lugging the motor keeps line pressure down and allows friction and heat build up.

 

[Snow man]

Matt, I know it doesnt make sense,and usually you are correct,but with the torque curve of the cummins(especially with a torque plate,or fueling box),and the way a chrysler auto works(line rise,and the way it shifts,only 1 overrunning clutch in the main trans,it all combines to make a light footed trans more likely to burn up in most cases.

a light footed chrysler auto will take more time to shift between 2nd and 3rd gear,since 3rd pushes off second in the chrysler auto,this means the 3rd clutches,and 2nd band will hang longer,and the overlap will burn 3rd faster than a heavy footed driver will,his shifts occur quickly and positive since his foots in it,hes got lots of line rise,RPM,and pressure. When used with a box or torque plate, the problem gets magnified because now you have the same power at 1/4 throttle that you used to at 3/4 throttle,yet you only have a small amount of line rise. So pressures are lower than stock for the same amount of power as stock. Now a light footed driver waits for the tc to lock then pushes lightly on the throttle,even towing on grades,with a box or plate, this is all ok if your trans is modded for it,but a stock trans isnt and this is when it slips,on hills, rolling into it in lockup. A heavy footed driver nails it it pops out of lockup,or even if it stays in,hes got full line pressure and more RPM since it probably dropped a gear. The Cummins motor at 1500-1700 can hurt the stock auto real easy,even mildly bombed motors. Light footed guys LOVE that RPM range,us heavy footed guys use throttle,rom and fluid coupling to get up to speed then lockup to cruise,a light footed guy goes easy as he can til it the tc locks,then they try to accelerate in lockup(this keeps the motor quieter,and revvinng less)this isnt conductive to long trans life. Most of my friends drive there trucks hard all have over 100K on them and no one has had to rebuild them. However i see guys who baby them burn them up much more often. Ill keep driving mine like I stole it,its way more fun

 

[OPoole]

the 48re input shafts would be a limiting factor. for you stock trans guys you sould be concern will the 48re rear trush bearing wear aroud 15,000-20,000miles there dead. call DTT 1 866 504 4002

 

[Matt400]

Hrmmm I guess I better snap out that mode!

That all sounds right except for the RPM thing cuz pressures are regulated and testing for full pressure the way I understand is at 1600 rpm but you also have to have the trans throttle lever at WOT.



Being light footed I see now will have the trans throttle lever in a position that would give less pressure. Thanks for the eye opener