Trans goes into limp mode

[Larry93]

[I] have a diablo predator set on 2nd stage it keeps going into limp mode after shift down while towing trans code is a700 and it will clear but the next hard shift it does the same thing.At this rate I can't tow unless I take the tune out, The truck is a 2002 with 60k on the clock. Thanks Larry

[Kennedy]

How long have you used the Predator? Is this a new condition?

How many miles since the Allison spin on filter was changed?

The second setting as I recall is 60HP with that Pred and while far from a stellar tune should not harm the trans.

[Larry93]

Thanks for the reply John.I have had the tuner ,diablo, for three years or more normally run on stage one 40 hp. truck normaly has a 3000 lb. slide camper and maybe the bike trailer and Bike for a load. Never more than 8000 load. WEnt to the 60 hp stage two and so far have went into limp mode twice and thrown code P0700 each time. The truck has 60K easy miles. The trans spin on and pan filter were serviced just before i went to the stage two settings about 7000 miles ago. the truck is an 02 LB7 Larry 93

[More Power]

Some Allisons are better at handling power/tq than others. Most can handle 75-90 additional hp without a lot of complaint, some can't. Assuming the ATF level in the trans is where it needs to be, you may have but two choices: 1- run no more than the lower Diablo power setting. 2- Put some money into the transmission.

A couple of years ago I communicated with a member who's 2005 LLY Allison was setting trans codes when using 60 or more additional hp. This particular trans had set a code early in its life at the stock power setting, so it was likely not up to par from the beginning. Towing heavy with 60hp pushed the owner into a performance trans rebuild. Then he was happy... ;)

Jim