With tow/haul button, who needs a clutch?

[gambler]

2nd gear lock-up

Apparently the '04, 305/555 & the '04. 5 325/600 electronics are different. I don't know of anyone with the 325/600 48RE that locks up in 2nd gear, so the trans. electronics must be different.

 

[edgrim]

According to Dodge the 48RE can be locked in 2nd, 3rd,and 4th gears so he's right! Just select 2nd gear make sure tow/haul is also engaged.





Thanks for the post kober.

 

[XJSuperman]

Right... but you are missing my point. I know the 48RE will lock up in 2nd over 25MPH... as well as in drive and OD over 49 MPH... I had an '04 automatic up until 3 months ago.



BUT... this is while on level ground, or going uphill... etc. This guy is also talking about COASTING (downhill if I understood correctly) in 2nd gear which means he's attempting to use compression braking with an auto trans... he's NOT putting line pressure through the trans so the converter isn't locked.

It's like you're on level ground... at say 35MPH in 2nd gear... . sure... holding it in 2nd the converter will stay locked... until you let off the pedal. Once the pressure drops enough the converter will unlock.

He was towing a fairly good load going DOWNHILL in 2nd gear... I seriously doubt under those circumstances the converter was locked.

 

[BIG BOB]

What I have notice with my 04, 555, 48RE is that it does lock up, however when rpm go below 1500 the TQ unlocks.

 

[KCJackson]

Here's the scoop (so to speak)



With the 48RE, the T/H button depressed when in "D" shuts off overdrive. When in the "2" position, it allows the TC to lock when below 50.



With the 545RFE (used with the Hemi Ram HDs), pressing the T/H button <B>actually changes the shift points</B> as well as controls TC lockup. This is the same function as T/H with the GM/Allison and Ford/TorqShift.



Because the 48RE is so "old" - it's still based on the technology of the TorqueFlite 727 - it can't change shift points on the fly like a modern electronic automatic. If the upcoming 5-speed automatic ("58RE" for argument's sake) is still based on 727/48RE technology, it won't change shift points either unless there are major reworkings internally. If they make a clean-sheet "58RFE" (in Mopar trannies, FE stands for Full Electronic, as opposed to just E which signifies electronic control replacing the hydraulic shift), then I would expect T/H to be able to make dynamic shift point changes like its little brother 545RFE and the competition's heavy automatics.

 

[BHunt]

TSB-18-007-04 does this:

"allows automatic transmission equipped vehicles to lock the torque converter clutch when a manual 2nd gear downshift is selected. "

Hope this sheds light on the sitiation!

 

[jsimpson]

Guess the TSB explains why some do and some don't. The 2900 in 2nd gear suggests that it's locked up and not coasting. Now if I could just figure some way to get it to ALWAYS lock up in second and third, even on upshifts, then I'd stop being jealous of my brother's Allison!

 

[XJSuperman]

SO am I right? The question (for me anyway) is NOT whether the 48RE from '03. 5-'04 locks up in 2nd... we know it does.



The question is... does it do it while COASTING??

 

[jsimpson]

I want it to lock up in 2nd and in third while in DRIVE!!!

 

[kober]

SO am I right? The question (for me anyway) is NOT whether the 48RE from '03. 5-'04 locks up in 2nd... we know it does.



The question is... does it do it while COASTING??

I think you found the answer in the manual a few posts ago "... When this conditions occurs, press the TOW/HAUL button or shift into a lower gear to prevent excessive transmission wear and/or overheating,and to provide better engine breaking. "

 

[RankRam]

SO am I right? The question (for me anyway) is NOT whether the 48RE from '03. 5-'04 locks up in 2nd... we know it does.



The question is... does it do it while COASTING??

Mine does lockup while coasting.





This thread is getting out of hand. :-laf

 

[jsimpson]

I think you found the answer in the manual a few posts ago "... When this conditions occurs, press the TOW/HAUL button or shift into a lower gear to prevent excessive transmission wear and/or overheating,and to provide better engine breaking. "

I sure hope it said "better engine BRAKING" ! :--)

 

[Flores]

I will check my manual again.



ILL BE BAAAACK :-laf

 

[Flores]

Press the tow/haul button or shift into a lower gear to prevent excessive transmission wear and/or overheating,and to provide BETTER ENGINE BRAKING.

Page 282 of the 2004 manual. Early manual that is. Doesnt say anything about the 600.

 

[kober]

I sure hope it said "better engine BRAKING" ! :--)

LOL! Course it does! That's what I get for copying and pasting other peoples posts ... .

Kurt

 

[kober]

Press the tow/haul button or shift into a lower gear to prevent excessive transmission wear and/or overheating,and to provide BETTER ENGINE BRAKING.

Page 282 of the 2004 manual. Early manual that is. Doesnt say anything about the 600.

The manual in my glove box said the same thing ... .

Kurt

 

[Lorenz]

well i was going to post the link to TST lock up switch (mystery swithch) but they moved it or removed it. any ways... you can lock up your TC in 1,2,3&4. yep 1-4. the directions warned of stalling the truck if you came to a stop with the swith engaged and TC locked.



It involved a jumper wire in the fuse box replacing the transmission relay, and a switch connected to an orange/blk wire on the firwall to a ground source. grounding the orge/blck wire would lock up the converter.



the link is gone but i printed it out. if there was any intrest id go to the trouble of borrowing a scanner and posting the directions/diagram.

 

[Flores]

SLorenzen,your dad paid me a visit a couple weeks ago. Did he give you the hose clamp for the boost elbow?I was so sure it was your dad on this forum!!It took me a while to locate these clamps and was only able to buy them in a bag of 100. Anyways... ... .

 

[Lorenz]

no, the bumb must've kept them, that or he forgot. probaly the later. he told me he talked to some one on the forum last week. thanks for the clamp. nice to meet you... . in third person anyway!



did you end up trading in the ca 04 for a newer 04. 5? tow haul mode was on the new 600 model right?

 

[hasselbach]

You can engage the 2nd gear lock up by putting in 2nd (regardless of tow haul) and blipping the throttle, it will lock up sooner and stay on longer. Just by putting in 2nd does not guarantee lock up.

I've confirmed the earlier lock up and longer lock up with my scan tool. . Works great.