Allison 5sp: Newb Transmission questions & issues
- Thread starter raceghost
- Start date
I'm at 660+ HP to the tires and on all stock shafts. You'll break the P2 planet before a shaft it seems, since I ate one of those, and the C2 hub. It seems your goal is below my power level (if I recall correctly), so shafts would be a waste of money IMO.
I'm literally out in the garage right now assembling my transmission, haha.
I only went with a billet input for one reason: so that it doesn't snap off inside the converter, and thus pissing $1800 into the wind. My brother lost a converter with a broken input on his 4R100. I've heard of it happening with the Allisons as well.
So I just went with it for peace of mind. Doesn't sound likely that you'll break any of the shafts under 600 rwhp, but it was worth the extra $600 to me to know I won't take out a part that costs 3x as much if it does break.
I only went with a billet input for one reason: so that it doesn't snap off inside the converter, and thus pissing $1800 into the wind. My brother lost a converter with a broken input on his 4R100. I've heard of it happening with the Allisons as well.
So I just went with it for peace of mind. Doesn't sound likely that you'll break any of the shafts under 600 rwhp, but it was worth the extra $600 to me to know I won't take out a part that costs 3x as much if it does break.
Do the C2 hub. You won't need shafts. If the Allison input shaft breaks it is no problem popping out the broken piece. I've done it many times. No damage occurs to the converter.
And/or [THREAD=67680]broken trim springs[/THREAD]...
Relatively low, right under 1,000 lb-ft. I spin the motor a bit higher RPM than stock.
Indeed. I wish you had invented them a couple years earlier, so my first transmission build could have had them. My current one has them, and so far, so good.My trim springs don't break.
I guess I wasn't clear with how I phrased that. My old trans (which blew up from broken trim springs) didn't have the MikeL springs, because he hadn't invented them yet. My current trans does have the MikeL springs, and they are working great.well get some and put them in! same with the shift valve springs. you will like them
no you were clear. im currently running on 3 hours of sleep so things blurred together lol
It connects the C2 clutches to the P2 planet. They are know to strip the splines because they are made of soft metal.
Is the stock Allison input hard enough, that it breaks clean enough, that it'll actually come out?
I know my brother's 4R100 builder tried and tried to get his broken input out, but it just wasn't having it. It was hard enough you couldn't drill / tap it, but apparently not so hard that the splines didn't deform just a touch inside the converter, effectively locking it in place.
Out of curiosity, what in the tuning causes the C2 hub to fail? A tie-up where the C2 is applying before C3 releases? Or just a harsh shift and resulting shock load?
A harsh shift is a tie up. Not knowing how to play with fuel tables will take out a P2 planet and C2 hub on the 3/4 shift.
Ok, transmission is ready and about to be installed. I was reading on here in another thread which I cant seem to find at the moment, about when you mate the Flexplate to the converter, extra precautions you take to ensure you don't do something wrong or risk a failure down the road.
Mike, can you give me any of your pointers on the reinstall of a built transmission please. I believe it was one of your posts I was referring to. ANy help would be greatly appreciated.
Mike, can you give me any of your pointers on the reinstall of a built transmission please. I believe it was one of your posts I was referring to. ANy help would be greatly appreciated.
First, there is one square hole in your flex plate and it should be aligned with the starter opening. Turn the flywheel till it lines up. After you bolt the bell housing to the block, your converter must be free to turn easily. Draw the converter to the flex plate and install your bolt and tighten it. Then do the next 5 bolts.