93ToyKid

Is there a way to keep the torque converter on my 89 3.0 from locking up? On the freeway, if it were just in overdrive with no lockup, it would be at the perfect RPM. (I have 4.88s and 37s). Is there a wire you can unplug from the tranny, or a brake relay that tells it to unlock? Also, would this produce too much heat, since there will be slippage when on the highway with it unlocked? Thanks guys, just trying to find a way to help my faithful 'ol 3.0 get on down the road...........

93ToyKid

Edit: I just thought of something even better. Is there any way to have it lock up in third and keep overdrive off? That would be ideal. Thanks!

SD70MAC

I would say the best thing to do is get a different torque converter. One with a higher stall speed should solve your problem. I'm going to change mine out for one with a different stall speed because I can't maintain highway speed when it shifts into OD, I have to keep OD off just to maintain 75 mph. Changing the stall speed will change the RPM that the TC reaches coupling phase/rotary flow (lockup). Check around online for different manufacturers and see what they have for your truck, or call them and explain your situation and they should be able to hook you up.

toyotaoffroad91

to words "re gear"

ChickenLover

You can lock the TC up in third by simply turning o/d off. Next time you are accelerating in third, click the o/d button off and you'll feel the tc lock up and the rpms will decrease by about 500.

93ToyKid

Thanks for the replies! Yes re-gearing would be great, but the gears are brand new, as my cousin installed them with detroits front and back right before we bought the truck. He put the 4.88s in it because then he had the option of running anywhere between a 33-37. It's not as dead as you would think it would be. If I can get the lockup thing to work as chickenlover said, it'll do just fine. I probably would have put 5.29s in it, but even then it probably wouldn't pull overdrive on anything except the highway, so it would be way overreving around town. Right now it's about right. O/D is only used on the highway.

Jeffires

On GM its easy- a buddy of mine has a switch in the console of his '85 442 that keeps it locked or unlocked whenever he decides. For my truck (only running 31x10.5), I would like to fix mine to where I can force it to stay locked- coming unlocked on slight hills brings up RPMs and is not necessary. If it would stay locked, it seems like I would just loose some speed rather than unlocking....

93ToyKid

Well we had thought about rigging up a switch just like you're talking about. Anyone know of any pros/cons to that?

Jeffires

I don't see what would be bad- I've driven his 442 and you can leave it unlocked or force voltage to the switch and lock it up manually in any gear, when you slow down to a low speed for that gear or punch it, it acts like a manual transmission (when forced locked). I don't know how good or bad it is for the transmission, as I haven't worked on auto's before.

MTL_4runner

It builds up alot of heat on the highway if you don't allow the converter to lock up.....not to mention you are eating up gas mileage too. If you have an OD button, just use that instead. If you don't, it would be far better to regear properly for the size tires you are running.