Refresher course on converter and lock up?
 

Just when I &quot;think&quot; I've got a handle on how best to drive LadyRam, I read something on the forum and say, &quot;Wait a minute, what does that mean?&quot;<br><br>Most recently it's been discussions on &quot;slipping the TC clutch&quot; and &quot;letting off the throttle just before lock up&quot;. <br><br>Does this mean letting off the of the throttel in 3rd? Letting off in OD just before it makes that &quot;whoomp&quot; sound after I unlock, and am getting up to speed entering the freeway? Does the &quot;gear change&quot; into 3rd (OD off) indicate &quot;lock up?&quot; <br><br>What is the relationship between OD off or on and lock up? I thought OD off was lock up and OD on was not? Now it does not seem that simple. <br><br>Told you I am confused, again. Can any one comment on this in a way that I might finally get it?

Re:Refresher course on converter and lock up?
 

Ladyram, &quot;lock-up&quot; is a term meaning the torque converter part of the transmission &quot;locks out&quot; the torque converter and goes to a direct drive type function. What happens is the transmission goes from 3rd to overdrive, and then at the proper load level on the transmission, the overdrive will enable the &quot;lock-out&quot;. You will not get a torque converter lock-out with overdrive turned off. The idea of the lock-out was to reduce power loss in the transmission by &quot;locking out&quot; the torque converter and going to a more direct drive to the drive shaft. Does this help?

Re:Refresher course on converter and lock up?
 

Ladyram, When you pull out you will feel the shift to 2nd then the shift to 3rd and then the shift to overdrive and then another shift, this is when the torque convertor locks up. Just let up on the throttle a little so it will lock up easier/quicker.

Re:Refresher course on converter and lock up?
 

LadyRam,<br>The TC will lock in both 3rd, and OD gears. If you start from a stop with the tranny in D, O/D off, you will notice a shift from 1-2, 2-3, then you should see a slight drop in rpm's when in 3rd, this is the TC locking up. If you are cruising in 3rd with O/D off, shift into O/D, you will see a slight jump in rpms (TC un-locking), then the trans will shift into O/D gear, then you will see another slight drop in rpms (TC locking up). I guess to answer your question, the O/D on/off button does not simply control TC lockup. <br><br>Someone will correct me if I'm wrong... Hope this helps!<br><br>Russ

Re:Refresher course on converter and lock up?
 

That's exactly how mine works.

Re:Refresher course on converter and lock up?
 

Thanks for the replys. It is much clearer now. I am up to speed on the shift points from 1-2 and 2-3 and the shift into OD. Now I will pay close attention to the &quot;rpm drop&quot; in 3rd and OD.<br><br>From other posts I've read it's when this &quot;rpm drop&quot; ocurrs that I should let off the throttle. Right? I guess when I'm out tomorrow I'll have to pay close attention to this new little move. I know I have never paid attention to this aspect before. Especially when kicking into OD when entering the freeway. I hope I have not already done 15,000 miles worth of any serious damage. <br><br>I think it would be great to have computer voice boxes in our Diesels that talk to us and keep us informed on what's going on under the hood. Something like, &quot;OK we're locking the Torque Converter now, back off!&quot;<br><br>There is a lady that lives in my home computer that gets on my case when I'm messing up. ;D ;D ;D ;)

Re:Refresher course on converter and lock up?
 

Sounds like you have it under control now Ladyram. I agree on the voice box telling you what it is about to do for you, but with the older gens, you wouldn't be able to hear it anyway.