Which was featured in Diesel Power this month uses a Dodge 47RE built by Sun Coast that handles the power of the truck...

I am not too keen on how transmissions stack up against others, but the Allison and Ford trannys seem a lot beefier than the Dodge units...

Why wouldnt a built Allison hold the power, but a Dodge would?

 

I think the problem is getting the Allison to shift quick enough. It is computer controlled and slips too much when shifting during a race. The Dodge tranny shifts harder and faster with a modified VB, higher rpm and more throttle. They are governor controlled with variable shift intensity.

It's not so much that the Allison is weak, just slow to shift. Also the 1st gear ratio is way too low for racing. The Dodge trannies get a bad rap because they get abused and are not meant to handle more than stock power. But with a few mods they easily will handle more. Dodge only puts in parts that are strong enough for stock power, not as strong as they could be, so guys slip them and burn them up or break shafts with high HP violent shifts. Then they complain that the tranny is junk. No, it's just not built for the added abuse, but can be.

 

Exactly, just look and see what trannies most of the big HP trucks use.

 

I have explained this many times. I will try to find a post where I explained it in detail/

The stock allison hard parts are MORE than up to the task, its the operation characteristics of it that hurt it. Just cant make a clutch to clutch trans shift fast without self destructing.



ben

 

https://www.dieseltruckresource.com/...31&postcount=9

https://www.dieseltruckresource.com/...3&postcount=11

https://www.dieseltruckresource.com/...2&postcount=12

some reading for those who are interested.

ben

 

Its not the input shafts that generally matter, billet shafts are pretty hard to break in all 3 of those tranny's... However, the 4x4 output shafts break in the Allison even if they're billet parts.

They were great trans for what they were built for, but their design limits their maximum capabilities.

 

im talking about stock input shafts. A stock allison input shaft will take twice what a 47/47re one will.

I would like to see a billet broken output shaft.


thats what I said. Billet parts are not going to help an allison because the shockload created when a tie up or bad shift occurs will destroy even billet parts.

 

Can't you reprogram the TCM to make it shift faster?

I don't understand how the innards work and I've read the posts you linked to.

You have a Allison for Dummies version?

 

[QUOTE=duratothemax;2373005]
I would like to see a billet broken output shaft.
QUOTE]

Basically the Allison parts are beefier in size but metal wise similar to 1040. The outside is chem harden but uses a cheaper steel. It just isn't cost effective for the aftermarket to involved with things like what is most needed P2's and associated ring gears... However, there are some builders haveing real good luck lately and we also have a couple guys that can program the tranny unlike the others via efi live. But once the 850+ hp is made all bets are pretty much off on how many passes can be made.

The Dodge 47/48RE aftermarket parts availability is a monster that gets stronger with every passing year.

P.S. Your right no broken billet outputs yet but below is a pic of where the stock ones fail.

 

[QUOTE=OPIE;2373715]But the 47/48RE use 40yr old tranny technology, so you can't compare it to the Allison.

 

Depending on the year, I've heard somewhere that the Chevy's have some kind of torque management on the tranny that will take away power from the motor shifting from 1st to 2nd, then slam it into the rest of the gears. It causes to truck to fall flat on its face, then blast full power to it.

Maybe that could be why?

 

So you mean the Allison isn't gods gift to the auto world




You should tell that to all the ignorant Chevy guys around here that seem to think its the only tranny ever built.
DS79

 

I never said it was. It is a hard to beat transmission in a "stock power work-truck only towing huge trailers all day across the country through varied terrain" application. Racing or more than 750rwhp, forget it. You are on borrowed time no matter how built up it is.


Yes there are some chevy guys who fly the allison flag way too much, the allison is gods given gift to the transmission world............but there are also dodge guys that do the same thing with the cummins flag...

just my opinion

ben

 

But the Cummins is King! You Dmax guys just haven't figured it out yet. J/K I would drive a Dmax if the price was right and I needed a DD diesel. They make way to much power with just programmers and simple mods to say I wouldn't want one.
DS79

 

but why did it take 40 trannys to switch. I would have changed after number 2