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Lugging a T/C... Bad for it?

1K views 6 replies 5 participants last post by  1workinman 
#1 ·
No no no, I'm not running a manual lock up switch and Im not rolling coal on kids on sidewalks.

The PO of my truck (a friend) told me that when he got the tranny rebuilt he was told to install a 'tugger kit'. Not 100% sure what that even means and honestly I can't find all that much info on what that could be, but what I do know is that if my truck finds T/C lockup (in 4th or 3rd) it will hold lockup until theres not enough fuel to fire the turbo, its smoking like a train and trying its hardest to stall unless you let off that gas and let the gear kick down. Drove my buddies truck which he is 100% sure does NOT have any sort of 'tugger kit' and it won't do this, it will unlock if it gets even close to as low as mine if you want it to or not.

So my question is, is that something I should avoid? I never let it lug way down in over drive but where I live and tow there are LOTS of hills, and when Im in 3rd lockup and going up a hill and it gets to seriously low RPMs and starts to lug I am assuming I should let off it so it can shift? I do not try and make it do this it is just how the truck drives and the situation that happens now and then (not a daily thing). Wanted to know if i could be destroying my T/C by letting this happen.

Thanks guys
 
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#3 ·
Double check that your TV cable is properly adjusted (according to FSM specs) to get your kickdown back, and if it won't spool in lockup, check your preboost. You may have too much, resulting in the injectors putting out the fire, or not enough preboost fuel.

Google shows a "tugger kit" is some kind of valvebody mod. That said I'd never heard of it until now.
 
#4 ·
Ok maybe I shouldn't say IT WONT FIRE THE TURBO, but it will lug low enough that the turbo just barks and smokes on and off like crazy. But I also think it may have something to do with my non-functioning waste gate. I have the feeling that it is just a bad combination of smaller things making it act like that.

But for the original question, is lugging the T/C like this sort of bad for it? Really bad for it? Fine for it?

Thanks
 
#5 ·
as rpm,s decrease toque increases per given hp. that means it is putting more load on your tq. it is always better to run in a lower gear and keep rpm,s up to lesson load on drivetrain. how much will depend on who you are asking.
 
#6 ·
Transmission pump oil output (volume primarily, but pressure to a point) scales directly with engine RPM. It is possible for your low engine RPMs to not let the transmission generate enough pressure to keep the clutch packs or TC clutch locked together. I would expect this kind of thing out of a turned up truck with a stock valvebody, but if yours has a shift kit it's probably okay.
 
#7 ·
I will make a suggestion here never lug the engine . I don't do that for a couple of reasons for one egts can get out of hand , I like to keep up the oil pressure in the transmission . Seems many years ago I was told the oil pump was 3.9 gallons per min and it went to 4.2 in later models . Of course keeping leaks to a min is best any way . Regardless I watch the egt gauge and boost gauge. I shift when towing to land my shift at least 1600 or better 1700 . 750 gear splits . Lugging is not for me , but that is just my option Jim
 
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