I have an LLY that I just replaced the allison on with a stage 1 ATS allison. Long story short the tranny just couldn't do what I was asking of it.

I also own an LB7 that I would like to avoid the same trouble with. I have between $2700 and $3000 to spend to achieve this goal. My question is this:

If I were to add a shift controller (like the CoPilot) to my stock Allison is my stock torque converter going to handle the extra pressure, or would it need to be replaced also?

I have an LLY that I just replaced the allison on with a stage 1 ATS allison. Long story short the tranny just couldn't do what I was asking of it.

I also own an LB7 that I would like to avoid the same trouble with. I have between $2700 and $3000 to spend to achieve this goal. My question is this:

If I were to add a shift controller (like the CoPilot) to my stock Allison is my stock torque converter going to handle the extra pressure, or would it need to be replaced also?

What was the ATS not doing for you that you wanted it to do?

For 3k I would do a stage III kit and be done with it.

The original Allison in the LLY was the one that was giving me trouble, the ATS (once ATS gets it right) should be fine like it is but I may add a CoPilot to it to make it a stage 2.

Anyway back to the LB7... a stage 3 would be $6100 + installation, that is out of my budget range. The stock Allison is in good shape and has never been limped so what I am trying to do is to considerably extend it's life. No sense in replacing a tranny that isn't trashed yet IMHO.

That brings me back to my original question, if I were to add an ATS CoPilot to the original Allison to increase line pressure, would the stock torque converter handle it?

It's not a matter of pressure....It's a matter of torque. How much power are you going to be throwing at it? What are your goals for your truck?

Anyway back to the LB7... a stage 3 would be $6100 + installation, that is out of my budget range. The stock Allison is in good shape and has never been limped so what I am trying to do is to considerably extend it's life. No sense in replacing a tranny that isn't trashed yet IMHO.

I dont know where the $6100 came from, but a stage III suncoast kit w/converter was just over $2k IIRC. Add another 1000-1500 for install and be done.

When I said stage 1 I was reffering to ATS's stage 1, so I assumed he meant ATS stage 3. Thanks for pointing that out, I will look into it.

I use the Preditor towing tune on both of them right now which is 40 extra hp and might use the 65 hp tune but that would be it more than likely.

I think the suncoast would be right up your alley, with what it does, it will also give you some room to improve the HP and not have to worry about your trans holding up. Maybe just a transgo shift kit for the trucks if you dont plan on going too much further HP wise.

Stock trans will handle a 40hp tune just fine. If your LLY trans failed with the 40hp tune I would bet that there was an underlying issue that caused, or greatly contributed to the failure.

Dropping $1200 on a co-pilot seems to me like putting a very expensive band-aid on a gun shot wound.

If it were me, I would put that $3,000 in a safe place, and call it your trans fund. Then when the time comes, you have the money do the upgrade. You said it your self....
No sense in replacing a tranny that isn't trashed yet IMHO.

I don't see the sense in dropping almost half of you budget on a co-pilot for a trans that has only seen a 40hp tune.

$.02 :)

How many miles are on the LB7? IMHO if the LB7 tranny is in good shape and you don't plan on getting too radical with it I would look around for a used co-pilot. I am not an expert, but isn't the weak part in these allisons 4th and 5th gear when power is added? The copilot will increase your line pressure, making the clutch packs hold more power. It is on ATS's website


"The ATS Co-Pilot Upgrade Kit for the Allison 1000 Transmission solves the major problems with the stock Allison LCT-1000. When you increase the power of the Duramax, the stock Allison 1000 transmission begins to slip in 5th gear. The factory single-disc torque converter lockup clutch begins to slip. This slippage causes the Allison 1000 to go into "fail safe" mode preventing you from getting your Duramax power to the ground. The stock Allison transmission only receives approximately 86 PSI oil pressure to the clutch packs when in 5th gear.

After the addition of the Co-Pilot transmission system, the clutch packs receive approximately 230 PSI, allowing the transmissions clutch packs to receive full line pressure (clamping force needed to apply the clutches) during high power situations. With the simple addition of our Co-Pilot transmission kit pushing the available line pressure to the clutch packs, we have designed a system that increases the torque capacity of the Allison transmission by over 200 foot pounds. This kit makes it possible to transfer 100% of the power developed by a modified engine to the rear wheels without causing the transmission to slip and the "fail safe" condition to occur."

rader2146,

I suspect you are correct about the LLY although it does the lion's share of the towing between the two. It is not uncommon for it to tow 10k-15k lbs. over 7%+ grades. I have considered doing exactly that with the money also but figure $ 2700 now is better than more than double that later.


zlonsway,

The factory single-disc torque converter lockup clutch begins to slip. This slippage causes the Allison 1000 to go into "fail safe" mode preventing you from getting your Duramax power to the ground. Exactly why I ask if the factory converter should be changed at the same time.