mudbuster

I have been driving the same truck to the same job for many years now. The exit ramp off the highway is a long straight one with a turn at the end. I will say I am going 65mph because I am sure that I would never knowingly exceed the posted speed limit, anyway coasting down the ramp at 75 my truck does not slow down as much as it used to, but my rpm's do seem to fall. Do torque converters wear out like this or do I have other problems..... I should specify that this is a 3 speed 727 with 307 gears.

j_martin

Happened to me with a Goerend low stall converter. One reason I installed it is that I rely on engine braking with an exhaust brake for downhill control of the double trailer rig.

I was told that the coupling between the pump, stator, and turbine is quite close, and is pulled a slight bit tighter by the forces generated by acceleration. Conversely, it is driven apart slightly by the forces of deceleration.

1. It's possible that worn thrust parts could open the gap enough to decouple it in deceleration. Acceleration would not be affected.

2. Probably the most common reason for this failure, at least in the 727 and A518 is someone put in a shift kit, which most likely will be a broad range kit that covers lockup transmissions, and put in the TQ pressure mod which is totally useless in a non-LU transmission, but can stretch the torque converter.

In my case, Goerend had us measure the converter for stretch, and we found none. They then opened it up and found no problem. Probably replaced a couple of thrust parts, and put it back together. (All under warranty) Mike, at NATCO, checked the valve body and found the TQ mod. He removed it. When he put it all back together it functioned fine.

I postulate that what was happening is that a combination of normal wear, and slight temporary stretching by the excessive pressure (TQ mod) caused the decoupling under deceleration.

mudbuster

My engine does rev up a bit taking off but not sure how much of a change this is, I just notice slowing down because of that long ramp I use going to work,I know these factory converters are pretty loose but there is a noticeable change over the last few months. Been thinking of a low stall converter anyway. Has anybody ever used a "monster transmission" torque converter?

j_martin

With the quick delivery of the exact converted I needed, determined by Goerend after I answered some questions, and the both fast and good warranty service, more than I deserved, I wouldn't go anywhere else.

BTW, it isn't a matter of loose or tight, it's a matter of design performance. With the stock converter I could burn the tires at will. It takes much more engine torque to do that with the low stall converter.

mudbuster

I will call them. Thanks for the input

Jim Lane

I do not think my truck slows down at all, (main reason for poor brake life) at 75 mph I can back off the throttle and the rpm's will drop to idle and the truck will slow down but probably more from wind resistance.

I can drop into low gear and bring up the revs and force the trans to couple and then I wil have some low speed control till I have to shift,

I would love to have an exhaust brake but the freewheeling converter prevents it from working.

Jim

j_martin

At 65 mph i can shift out of OD and engage the exhaust brake and hold steady downhill speed on about a 4% grade with 2 trailers in tow. Second gear will hold it back to about 40 on a 6% grade. East Homestake takes a touch or two on the service brakes to boot.

mudbuster

That is exactly what my truck is doing, decoupling when I coast, but it didn't always. I spoke to Goerend today and they definitely knew exactly what I was talking about, however they are out of my price range. That is impressive engine braking, especially for a non-lock up. I would love to be able to have that, even though my trailer is not as heavy as yours. Just curious, what does your engine brake sound like? A mini version of the big rigs?

j_martin

Not too macho at all. Inside it sounds like the engine is roaring due to the extra compressive load, but at the pipe it hisses like a snake.

I don't care what it sounds like, I just like to be able to keep the truck under control. Do you have any idea what it would cost to have a tow pick my triple out of the pit at the top of a runaway ramp?

In the works is a toggle switch to enable the exhaust brake and disable overdrive (if it's enabled) with one move. Same switch will disable the exhaust brake and enable overdrive with one move. Will take a little logic, not too much.

mudbuster

Well my new torque converter came in. A 1400 rpm stall. Going to put it in it tomorrow, wish me luck......

mudbuster

Well I took my tranny out to install my new torque converter and I had the wrong front pump seal. This is my transportation to work so I did not change it(matched it up before I took the old one out) and reassembled. It was not leaking before so I hoped for the best. Everybody reading this probably already guessed it but its dripping. Kinda upset at the parts store......

mudbuster

Well I took it apart again and replaced the seal. No more leaks.... Just for the info Goerend had my full confidence talking to them but wanted $650 plus shipping, $300 core charge. I bought a Monster transmission torque converter $425 free delivery, no core charge. I am happy with my purchase so if you are on a budget like me then I recommend Monster transmission.