So dumb question... I asked around a bit and got yes and no answers about this.

Me and a friend were contemplating building a cheap dirty mud truck. Nothing fancy or to compete with, but rather just a fun beater to tear away at some mud. I'm talking cutting and welding and hack job lol.

So far we're thinking of using a big old caddie or Lincoln car, something big.. and dt466 for power, and axles from the junkyard off a Ford super duty.
Probably a chain drop case and full time 4x4.

Through prior research, it seems like we can get quite a bit of power from the dt466 for cheap as long as we're ok with it running like crap. That's fine because it will be an off road only vehicle.

The only expensive challenge we see is of course the transmission. Most of the time the dt466 comes with the Allison at545 or a manual. A manual isn't any good for mud pits and the Allison auto will likely fall apart? Maybe it would be alright? Not sure. Anyways, we have the thought of connecting the engine straight to the allison without the tq converter, or removing the tq converter and welding it solid somehow. If we did this, we'd use the chain drop case to gear it down probably 50%. So in 4th gear it would only hit maybe 40 mph.

The question is, putting it in gear with no tq converter, I'm assuming essentially it would be like just dropping the clutch on a manual in 2nd or 3rd gear. With a 50% gear reduction, and a fairly light vehicle, I don't think this would be so terrible. I mean it would be totally impractical for an on road vehicle, but anyone have thoughts if it's practical for an off road beater?
Any guesses how long the transmission would last like this?
And if it ends up getting stuck, the situation may arise where we'd have to Rev it up a bit in neutral and drop it in drive. Is this certain death quickly? Or should it be fine for a while?
Keep in mind this is like a 500$ transmission so not expecting years of trouble free use from it lol. Maybe 20 hours of use per year.

Just curious because without the tq converter, more power should get to the ground, without so much tq on the transmission. So if it can live through the shock of going from neutral to 1st gear, it may live longer right?

Maybe it's best to just leave the tq converter alone and hope for the best? I don't know lol. Anyone ever seen this tried before?

 

It will break early and often. Use a torque converter.

 

That's wrong. It's called a torque converter because it converts RPM to torque. If the engine puts 500 lb-ft of torque into the torque converter, you'll get approximately 1000 lb-ft out of the torque converter and into the trans at launch. So if you remove the torque converter this is going to be a dog until you get the speed up.

Because of the shock loading into the trans without a torque converter I'd expect it to live a shorter life, not a longer one.

I doubt anyone has tried this because it just doesn't make sense.

 

I know you're the tranny guy but this makes no sense. It's not physically possible to add torque without leverage and you can't create leverage without a stationary point. The torque converter has no leverage.





As far as the other stuff, don't think what your suggesting as a good idea at all, there's no reason for it nor would it work well.

That said back in the day drag racers used to take a simple tough tranny like a powerglide or 727 and replace the torque converter with a clutch. I've seen it but I'm not up on the details of it.

 

The stator inside the converter adds the leverage. https://en.wikipedia.org/wiki/Torque_converter

 

So you don't know how a torque converter works, but you say I'm wrong. SMH. Most of the rest of the people on this board understand. Go read about how a converter works. 70f100longbed posted a good link.

 

We ran the GM Power Glide straight no converter, cooling lines looped, in a UMP Modified. Heat races are 9 laps, Features are 25 or 30, hammer down and feather the corners on dirt.


You have a total different animal.

 

With a clutch or not? The clutch in front of an automatic lasted a short time in drag racing.

 

No on the clutch.

 

Hell won't it stall everytime you come to a stop????

 

theres always neutral 😉

I still think it could be a viable option in certain situations .

 

https://www.raceny.com/smf2/index.php?topic=22419.0

 

Back in the days, BM made transmissions from I think all the major car company's that they removed the torque converters from and even the bellhousings on some, then added a special adapter pump housing and front pump drive system that engaged with the clutch release fingers.
The good old "Turboclutch", "Clutchflight" etc. So it can be done, but using an Allison it would just be more cost effective to keep the torque converter.