Is it true that our auto transmissions don't reach full cooling capacity until lockup in 4th gear? I have not got my Posi-lock installed yet and I doing a tow with my travel trailer this weekend. So when going up a paved steep road that would normally be in second gear for a few miles. Should I disconnect the vacuum line and run in 2 wheel drive low range in 4th or 5th gear for optimum cooling of transmission? I don't have a Trans temp gauge yet to monitor.

My wifey's Dakota has a 3 speed with 2 overdrives and TC lock up. 2nd gear has 2 gear ratios, one for accelerating from a stop and another for downshifting into passing gear. I still cant get used to it.

my 05 48re 4 speed thats what the ATSG manual says unless its a misprint! Kidding but it is a 4 speed

Joecool You could add a lockup switch, it would allow you to have 2nd gear lockup, that would keep temps down if your climbing some really steep grades and give a little engine breaking when it's time to come back down the hill. Very little cost (10$) and a hour of your time. One of the best mods I've done for towing.

Joecool You could add a lockup switch, it would allow you to have 2nd gear lockup, that would keep temps down if your climbing some really steep grades and give a little engine breaking when it's time to come back down the hill. Very little cost (10$) and a hour of your time. One of the best mods I've done for towing.

Don't you have to pull the VB and plug off a port, or is there another way to do this?

Don't you have to pull the VB and plug off a port, or is there another way to do this?

There is another way. http://www.tstproducts.com/Torque%20Converter%20Lockup%20Switch.pdf I didn't like it, but thats just me. I had one on my old trans before the ATS trans. The new 5star converter is efficient enough for driving around town I don't really worry about lockup, and it was hard on the rest of my transmission when I had the switch. I could see it having a place though, but I would worry about slipping it and burning up the converter clutches, especially downhill on a stock converter and valve body.

That's the standard lockup for 3-4 gears, bcbigfoot was talking about 2nd lockup

There is another way. http://www.tstproducts.com/Torque%20Converter%20Lockup%20Switch.pdf I didn't like it, but thats just me. I had one on my old trans before the ATS trans. The new 5star converter is efficient enough for driving around town I don't really worry about lockup, and it was hard on the rest of my transmission when I had the switch. I could see it having a place though, but I would worry about slipping it and burning up the converter clutches, especially downhill on a stock converter and valve body.

So using the jumper wire instead of the relay with a resistor in the ground wire must be what allows for lockup in second gear. I might have to change mine, second gear lockup could be very useful at times Sent from my DROID BIONIC using Tapatalk 2

The only way I've ever heard of 2nd lock up is by plugging a hole off in the VB. The method CSM linked is for 3-4 lock.up only.

I have 1,2,3, lock up and overdrive. Effectively 5 speed transmission. Am I the only one who can feel my truck to through 5 shift points?

No you're not the only one that can feel 5 engagements. Bottom line is that it is a 4gear set, period. The fifth is a clutch lock of the tc. Sent from my SPH-L710 using Tapatalk 2

The only way I've ever heard of 2nd lock up is by plugging a hole off in the VB. The method CSM linked is for 3-4 lock.up only.

The only way itll lockup in 2nd (w/o a vb mod) as wired my TST diagram is if you have the selector in "D" and flip the toggle after the 2nd gear engagement. Sent from my SPH-L710 using Tapatalk 2

The only way itll lockup in 2nd (w/o a vb mod) as wired my TST diagram is if you have the selector in "D" and flip the toggle after the 2nd gear engagement. Sent from my SPH-L710 using Tapatalk 2

Are you referring to the link CSM posted? I have had that same switch installed since I rebuilt my trans, it is only good for 3rd gear if the OD button is pushed in and 4th all other times. It will not lock 2nd. If you know of a way without plugging the port in the VB, I would definitely be interested. I don't feel comfortable going that route, I'd be afraid of whatever I put in there coming loose.

Are you referring to the link CSM posted? I have had that same switch installed since I rebuilt my trans, it is only good for 3rd gear if the OD button is pushed in and 4th all other times. It will not lock 2nd. If you know of a way without plugging the port in the VB, I would definitely be interested. I don't feel comfortable going that route, I'd be afraid of whatever I put in there coming loose.

As far as I know you are correct, factory valve body will only lockup in 3rd and forth with switch. Joecools was saying he had twin disc TC and I may have incorrectly assumed he had a built trans or at least a built valve body. Most built valve bodies that I'm aware are capable of 2nd gear lockup.