replaced converter

[Pont406]

Finally I replaced a converter and reseal the trans. Old converter was making power steering pump noises and was slippping. Replaced with a low miles tci 2500 stall that I got on a trade from my neighbour. My main consern was rpm drop from park to drive, now it's all good. Only problems now are spinning tires real easy and stall is 2900rpm. I saw a paper work on a converter and it was a 2500 stall but in my truck it stalls at 2900. So far it runs ok but I need to install an internal cooler soon. I also found out that my body mounts are done. Getting crossmember top bolts was major pita.

[Boog]

Now that's no way to use a repair manual, you know better than that! Does that sound like your Dad or what? Glad you got 'er going. What's next on the list? New tires?

[KB71C10BBSUPER]

Most stall converters are base on midsize cars. The lighter the car, the less stall (2200 on a 2500 stall), The heavier the Truck, more stall. @ 2900 RPM stall on a 2500, gear ratio & tire size come into play. If you have a Tach, what is your Cruzin RPM @ 55 to 65 if it is under 2900 or just over, you may end up smoking the fluid and then the trans.

[myraley]

Hi guys. Can I ask a question? Smoking the fluid? At 2900 rpm's?I dont understand. I have an auto trans, too, but what do you mean smoking the fluid?

[KB71C10BBSUPER]

If you have a 2500 stall converter, Lets say you have 3.07 gear ratio with big tires. At 55 MPH down the freeway your tach is showing 2400 to 2600 RPM. Thus your converter is not fully engauged. As with this converter that was discussed it does not (fully) engauges untill 2900. There for pryor to that the converter is slipping. So if your cruise RPM is below that, The converter will never fully engauge, Thus slip and generate heat & smoking the fluid.
Just like trying to take off from a stop with a clutch, and you only let the clutch out part way it slips. If you never fully release the clutch, It will smoke the clutch. Same priciple with a converter with a stall.
High stall converters are made for camed up motors that have a lot of overlap @ the cam lobes, thus producing a lope. They allow you to pull it into gear with out putting a lot of load on the motor. This way the motor can Idle (some what).
Hope this helps, it's early and I haven't had coffee yet.

[mrein3]

Originally Posted by myraley

Hi guys. Can I ask a question? Smoking the fluid? At 2900 rpm's?I dont understand. I have an auto trans, too, but what do you mean smoking the fluid?

A torque converter is what allows you to sit at the stop sign with your engine running in drive and the drive train not moving. It is escentially similar to two fans facing each other, one plugged in, the other not. If you have little or no air blowing out of the powered fan, the other fan doesn't move. If you speed up the plugged in fan enough it starts to turn from the wind of the powered unit.

Similarily in your torque converter, at idle, the powered side which is connected to your engine turns with engine RPM. At a high enough speed, the part connected to your transmission starts to turn.

A "stall" converter has a higher stall speed. In this case 2500 RPMs however in this application it is stalling at 2900 RPMs. Higher stall speeds allow your engine to apply power to the wheels at a higher RPM. Which usually means better launches.

The drawback is that a lot of heat is built up in the fluid while things aren't spinning. So if the owner of this truck is running around town at 2900 RPMs the transmission fluid will get hot. Hot tranny fluid is bad for the tranny. That is why the owner says he is going to install a cooler soon.

If I was running that configuration I'd have an external cooler in addition to the one in the radiator. PLUS I'd install a transmission temperature gauge to keep an eye on things.