davelinde

Can anyone point me to the mods (or existing thread discussing the mods) I may need on my 04 48RE to tow heavier? I just picked up a new FW that I hoped would start out at 11,000# -- well, it scaled at 12,660# right off and it surely put some strain on my trans. I just pulled I-80 from Ohio to NJ (moderate grades but still some grades) and each climb would start to heat my transmission. I've got a BD-Xmon tapping the ECM for trans temp btw.

Normally unloaded I run at ambient +100 degrees, when I pulled 10,000# (12'6"high) I'd run at ambient +110 peaking to +120. Pulling 12,660# (13'6" high) I was averaging ambient +130 with spikes higher - eg 215 average spiking to 230 to 240 on the grades. Oh yeah, before I towed the grades in OD and now I'm using TH too and the temps STILL spike.

Before I never really saw trans temps move much on the highway at steady speed and even now the truck is not revving on the grades it's holding RPM and speed fine at 60mph. So these temp spikes concern me just to keep the trans temps from spiking I was dropping to 55 or even 50mph and sometimes even at 50 the temp kept climbing until I'd started down hill again.

My first search foundthis thread

I have no interest in spinning the tires in all gears but I do want my TC locked up when the dang thing should be locked!! Would this mod maybe help me pull the hills? I mean... at speed is it possible that the computer is actually unlocking me and starting to shear up the fluid? Isn't it more likely that the stock trans is either wearing out (72K on the clock) or not even up to the task of towing heavy?

If a simple switch is not the solution -- what is the first mod to try? I'm actually not thrilled with the idea of a switch I need to hit myself btw - I like to be lazy if possible. Am I right to worry these temp spikes? Lots of people told me to get another cooler for the truck (not sure where to put it tho) but I'm thinking that at speed with at TC properly locked and able to handle the torque I SHOULD NOT BE MAKING THIS HEAT at all... am I right? I'm trying to plan this out 'cause I'd hate to drop a few grand in modding the truck only to decide I've got to buy a new dually anyway. Honestly... if the 6.7 had better economy I'd be shopping for one now but I'm not ready for that plunge yet.


Suggestions?

P.J

You could try a mag-tech deep(er) pan, more fluid is always a good thing. It's only another quart and a half for your application though.

240 is not good. Do you know where the reading is being taken from, before the cooler I suppose?

Diesel Doc

How hot is too hot on a auto? Big trucks run up to 300 in the diff's same in the tranny eaton says don't exceed 300. Chevy trucks temp guage reads to 300. I have been wondering what the limit was myself.
some Cat engine oil temps run at 220.

cincydiesel

240 is getting hot. Try a deeper pan and check into larger line and tranny coolers. The weight your pulling is not the problem.. Its the giant parachute thats killing ya

soulezoo

There are answers for you! None are really cheap though. Since you are towing and not racing, you don't necessarily need billet shafts, although an input is nice. A DD mag-hytec pan is nice (I have one) but once your fluid warms up, it is there, and the extra fluid is hot and you really will not see a big temp decrease. The lock up switch (I have that too) works great and does as you described above about keeping fluid temps down from not shearing. Since you already have an older tranny... Look at Goerend's website under the heavy duty tranny rebuild with the lifetime triple disc converter. He will build the tranny to be most efficient towing heavy-- a TC and valve body to match your use and Dave will only sell you what you need.

P.J

Here is a chart: http://www.txchange.com/heatchrt.htm


Has to do with what temps break down the friction modifiers, and how that relates to overall fluid life.

Diesel Doc

thanks I never thought to search for myself as I don't have any automatics anymore.

davelinde

see sig, already have the pan.

seen the chart... never could figure it out. Does that mean that if I hit 225 for 40,000 miles total I'm toast or if I hit 225 for 2 hours I will fail three years later? I've seen people quote that chart and say "if I EVER hit 220 on my trans I would tow the truck home and change the fluid immediately". The way I read it the fluid (which has a rated life of 100,000 miles btw) has a decrease life at high temps. Fine, I change out half of mine every 20,000 miles. Now what?

Marketing mumbo jumbo charts aside... I do agree - heat kills transmissions and should be minimized.

re: Goerend... I've heard numerous excellent things about him and if he weren't 1100 miles away from me he might end up the no-brainer solution to my issues. Still might be OK, 1100 miles is not that far. I'm hoping there are some East Coast rebuilders with good reps and good pricing though... I'm seeing parts pricing - what do the installs usually cost?

Some quick googling makes me think I'm on the right track and my TC is either slipping 'cause it can't handle the HP or maybe being unlocked on purpose by the truck (for reasons I don't get?). I still need more facts, info, experience and options here... I'm sure I'm not the first person to think this through. I see a lot of high/heavy 5'ers on the road and a lot of them have a 5.9/48RE in front.

Spooler

MidAtlantic diesel is on the east coast and he uses Goerend parts. A couple of places on the east coast you can go.

P.J

Schew, me neither buddy, been through that. The hand shaker works flawless for me.

soulezoo

Goerends has different authorized installers near you... basically he will ship you a tranny built to your specifications to the intaller you choose (like MidAtlantic for instance) and swap out the trannys and send back your core. The tranny you get from Goerends will have already been tested on a dyno to ensure proper function before shipping so you can have peace of mind on what you are getting.

davelinde

If I knew then what I know now....

I bought this truck January 04 and had considered the dually and manual trans.
Now I wish I had them both - but I don't.

davelinde

COOL! Yep running down to Maryland to get a trans is do-able.

I see the Goerend pricing on his site and it's not out of the question. Any idea what the install might run me?

wingrider

I was quoted about $500 for install labor from Dave...I'm guessing others will be close to that.

P.J

From what I have read over the years, you will be more than satisfied with the results from Goerends. They are a first class operation.