never limped it before, but this week maybe i limped it... maybe engine code... not sure.

few days back, i was headed up a grade at about 60-65. i plan for a hard pass, and bump up to edge level 3. i'm running a medium amount of LPG from the deluca vacuum system (which is a lot on any other system - 27 mpg hwy diesel).

i stab the accelerator, truck downshifts i start to get out of the hole, then wham.... never comes outta 4th. rpm's were not limited, but it wouldn't shift up. i thought i limped it. pulled over, turned off for a minute, fire it back up, shifts okay, but SES light is on. later that day, after a few startup cycles, SES light goes out.

couple hundred miles and a couple days later, i'm towing a trailer that weighs about 3,200#. i have it in TH. edge at zero (gun shy), and LPG on. no problems but SES light returns. i *think* that it was right after a got on an onramp on the highway and did a hardish acceleration.

today, SES light is out. it's thanksgiving, so i can't get the code read anywhere, i'll do it tomorrow.

in 5th gear, when the TC is locked there doesn't seem to be much slip readout at all when cruising along at highway speeds. maybe 1% when i roll into it heavy without downshifting. but... when i slow down to <60 mph, and give it juice, it downshifts and slip winds out. attitude monitor seems to freeze the high slip readout momentarily which was 42.5%. i'm not sure what's normal.

questions...

1) is 42.5% slip on a tow haul, locked TC downshift from 5 to 4 normal... or have i fried it?

2) any guesses on what codes i get? (i'll post tomorrow after i find out - i'm sure i'll have more q's). i'm wondering if my truck is comfuzzled because it's not giving as much #2 as it would expect because of the LPG supplement.

thanks in advance for the thoughts.

the slip readout gets all wacky when the TC unlocks. (around 45 mph when NOT in tow/haul) Its basically irrelevant unless the TC is locked, because if you think about it, you're getting 100% slippage when you are stopped, foot on brake, in drive. So dont worry about it until the TC locks up. If, cruising down the highway steady speed, the slippage shows more than 1%, start looking for a place to buy new clutches. 1% or so is OK if you are rolling into it hard, but it should not read that high just cruising steadilly. Yes, you probably did limp it, but its nothing to worry about, just try to let off a little right before it shifts into 5th next time...

---Ben

i stab the accelerator, truck downshifts i start to get out of the hole, then wham.... never comes outta 4th. rpm's were not limited, but it wouldn't shift up. i thought i limped it. pulled over, turned off for a minute, fire it back up, shifts okay, but SES light is on. later that day, after a few startup cycles, SES light goes out.
That was a limp.
P0700 and IIRC P0735?

Definite Limp mode.



Ben i see u got your hands on a suncoast iv did your ally finally decide it needed some viagra :lol:

.....Its basically irrelevant unless the TC is locked......

---Ben

but i had tow/haul engaged. TC was locked in 5th, and then it was locked in 4th after the downshift. does the TC unlock while downshifting?

also.... is the slip readout while TC is locked a good indication of clutch condition? i guess what i'm axsking is..... without slip (or with very mild slip on accel) in 5th locked am i okay? only 1 limp (i think... bought it used w/ 90k miles; 109k now).

thanks for the help.

TC unlocks on every shift

TC unlocks on every shift

You would have a noticable clunck on the downshift if it did not unlock.

Ben i see u got your hands on a suncoast iv did your ally finally decide it needed some viagra :lol:

haha Its still holding up just fine...But I really want more power (so thats why I bought a Suncoast IV) and although it holds a 90hp PPE tune and the Edge on 5 just fine without limping, I dont know how much farthur I can go...considering most guys limp it with the Edge ALONE!!! I cant wait to see how my clutches look. If they look "ok" then ill really know if GM gave me "something special" in terms of transmissions.

--Ben

....i'll post tomorrow after i find out.....


well.... the auto parts store that has a code reader says that the SES light must still be on for his to work. he said the fancier ones will work. i have a line on a tech II that i might be able to use on monday. will the tech II read codes after light goes out?

Yes

Predator and Quadzilla will also.

Monkey-

Mine did the exact same thing, hung in fourth and the TC wouldn't lock as well as getting the SES light. You shut it right down and cleared it. I kept driving, and when I got to a stop sign, she was still in 4th....pretty funny having to spool the turbo to even get her to move!

After I shut it down, all was well. After 3 start/stops, the light went out.

You're hosing your clutches just like I'm hosing mine. Just as everyone here predicted, we're both heading toward upgrade land. Now I can slip 'er in L3, LBF5....gotta be pretty careful.

Hopefully the full boat ATS for me in January.