TC lock-up

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Jun 6, 2008 | 10:39 AM

#31

mongo75

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Joined: Jul 2006

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From: Indianapolis

I never understood why folks ask about this mod? Is it to get it to lock up sooner? Mine locks at about 40, and stays locked until I get below that speed.

Jun 6, 2008 | 12:34 PM

#32

ernesteugene

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Joined: Jun 2006

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From: Fulltime RVer

Quote:

Originally Posted by mongo75

I never understood why folks ask about this mod? Is it to get it to lock up sooner? Mine locks at about 40, and stays locked until I get below that speed.

For towing a larger 5er, you're much better off with a capability to lock the TC at speeds as low as 15 MPH in 1st and 2nd gear. You need to manually shift into these gears to do this, but having the TC locked reduces tranny temps when you encounter slow speeds like for road construction or for climbing winding hills at slow speeds.

I used the BD TQ lock which has DIP switches that can be set to allow TC lock up down to 15 MPH and lower, and I towed that way for over 9 years with no issues. However, you should ease into the throttle to avoid slipping the TC when its locked.

Jun 6, 2008 | 10:35 PM

#33

DaveWilliams

Elder User

Joined: Jan 2006

Posts: 649

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From: Charleston SC

I also have the SP diesel setup and agree that the customer service sux...one word awnsers to lengthy questions..besides that I love my setup. I had an issue of it locking too early so I simply took the TC lock wireing off of it and use it to control the EBPV with my cruise switches. I emailed Jody about the TC lock of my 60 tow tune, he said "No problem with using the SP box to work the EBPV and using the DP to control the TC lockup" He said that mine locks the TC at 40 and unlocks it at 35, so essentially when I start down the 7% grade with my 9500 fiver, I simply kick off the OD, and it downshifts to 3rd gear and I push the Cruise off button for 2 seconds and the EBPV closes. I press the go pedel and the valve opens, I let off the go pedel and the valve closes back. I simply tap the cruise on switch and the SP box is disabled and the cruise works normally...simple as that..but it is NOT cheap by any means, but I like it...A lot!!

Jun 6, 2008 | 10:58 PM

#34

mongo75

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Joined: Jul 2006

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From: Indianapolis

Thanks for the explanation Gene!

Jun 8, 2008 | 08:09 AM

#35

redfire42

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Joined: Jul 2006

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From: Jonestown PA

Quote:

Originally Posted by dartol

For the TC lockup you only need one wire to the PCM and to the TC solenoid though... just the right side of your diagram plus power to light the switch.

I am still lost on this and didn't even do it yet. I was told if you wire it up wrong you can back feed power to your PCM and burn it up or something. I am not one for wireing so alittle more info if possable would be great. I will do this this week since I am on vacation.