Trans heating from servos

[zippy]

i've used the servo pin height checker (shop tool) and have yet to find a case where the pin length needs to be changed on a stock trans. when performing a rebuild and changing band brands or machining the drum as some do. most often pin length also needs to be checked on trans that come through as a core that you are rebuilding since you don't know if the parts in it are correct for the vehicle. i never use their pin end or grind to adjust the length, i order the proper length one from gm and if that doesn't cut it, i look for the other source of the clearance issue. if someone has done a servo on a stock trans and run into this being an issue, they likely have a rare case or didn't do something right.

[d_a_n_payne]

I went and got the codes checked. Ive got P0894, P1515, P0894. The first one is something about the trans. comp. slip, the second one is about the idle aux. inputs, and the third one is the same as the first.

 

I am going to drive back to my mechanic and let him read what yall think and see what he can do. So put up as many solutions or ideas you can think of.

[zippy]

P1515:

 

The PCM detects that the commanded and actual throttle positions are not within a calibrated range of each other.

The above condition is met for less than 1 second.

 

P0894:

 

DTC P0894 sets if the following conditions occur for three TCC cycles.

 

The TCC is commanded ON for 5 seconds.

The TCC is at 40 percent duty cycle for 5 seconds.

The TCC slip speed is 130-800 RPM for 7 seconds.

 

Important

The following actions may occur before the DTC sets.

 

 

If the TCC is commanded ON for 5 seconds, the TCC is at 40 percent duty cycle for 5 seconds, the TP angle is 20-99 percent and the transmission slip counter has incremented to either 1 or 2, out of 3 to increment the fail counter for the current ignition cycle, then the following slip conditions and actions may increment the fail counter for the current ignition cycle: These conditions must occur sequentially.

Condition 1

If the TCC slip speed is 130-800 RPM for 7 seconds, then the PCM will command maximum line pressure and freeze shift adapts from being updated.

 

Condition 2

If Condition 1 is met and the TCC slip speed is 130-800 RPM for 7 seconds, then the PCM will command the TCC Off for 1.5 seconds.

 

Condition 3

If Condition 2 is met and the TCC slip speed is 130-800 RPM for 7 seconds, then the fail counter on the current ignition cycle is incremented.

 

The above slip conditions and actions may be disregarded if the TCC is commanded OFF at any time as a result of a driving maneuver, sudden acceleration or deceleration.

[d_a_n_payne]

I dont have a clue what that means but maybe it will help my mechanic in someway. Do you think its installation problems or something isnt working right?

 

I dont have the yank converter.

[zippy]

i don't think it has anything to do with the servo's. i think it may be something from the pcm, although not specificly the tune, maybe something else. whatever it is, the tcc isn't liking it.

[d_a_n_payne]

By tcc, you mean torque converter? So, the tune isnt the problem? Would it be the harness or some wires that are "pinched"? As yall said.

[zippy]

i highly doubt the tune is the issue. wiring is a deffinite possibility. the tcc is the torque converter clutch....

[Bugsdad]

if someone has done a servo on a stock trans and run into this being an issue, they likely have a rare case or didn't do something right.

 

I see what your saying about the stock setup. I've never done a 2nd servo on a "stock" band(I don't use the billet 2nd servos anyway anymore). I've always used the powerband or the alto wide bands when doing performance updates. Both of which require tweaking to get the travel correct. As far as buying pins. Naw. I just measure the travel versus the existing pin length and make the correction no point in buying parts unnecessarily. I don't like the sharp point on the apply pins anyway. I've even welded material onto the end of the apply pin in cases where a .570" TV boost valve is used to slightly widen the contact point to spread the force out over a larger area to prevent punching a hole through the band. I also shim the anchor pin slightly so it goes every so slightly deeper into the band to help keep it from tearing the band right there.

 

I've been doing these for a while just not on SS's. Learned lots of little tricks along the way. ;)

 

I hope you get your issue fixed soon. Your mechanic needs to retrack his steps while it's fresh in his mind so he can find out what he did. You'll have a hard time telling him how to fix something when you don't know exactly what he did to get it to this point. You know he installed a servo lineup for example. But you may not know what all he did to put it in. Best of luck.

[Jonmalibuss]

I don't understand if all he was doing was installing the servos why in the hell he would pull or even lower the back of the trans?

[Bugsdad]

I don't understand if all he was doing was installing the servos why in the hell he would pull or even lower the back of the trans?

<{POST_SNAPBACK}>

When I say drop down, I don't mean remove the bellhousing bolts. What they'll do is take out a supporting transmission crossmember and just let the trans hang from the engine. When my Syclone was under warranty, they replaced the transfer case due to a broken chain. When they let everything hang, they broke my shifter cable, TV cable, and bent my fuel line where it's bolted to the side of the transmission. And they tried to give it back to me like that. See what I mean?

 

In many vehicles, the servo lineup is too close to the floor board, the frame or the exhaust.

An SS may not need it but almost every one other vehicles I've been under needed it dropped down to gain some room. Some mechanics don't think about loading the servo lineup in sections instead of the whole thing at one time. So they'll drop the transmission down to gain access to do it. Like I said, we know the guy put a servo in, but we don't know what exactly what he did to do it. He's gonna have to go back to the guy explain the problems and let the guy try to figure out what he did to cause what.

 

If guys are capable of doing the work themselves, it's usually the safest bet. It's your vehicle. You'll treat it like it's your vehicle.

[Jonmalibuss]

Lazy a$$ mechanics!

[BenKey]

If the guy removed anything other than the heat shield and the servo cover, never use him again - he doesn't know what he's doing. A servo change takes about 20 minutes, or so, and most of that is removing the heat shield. There is not any need to remove anything else.

 

Personally, I think you should have tried this one yourself. An intake change is harder. But, that's just me. I'm too cheap to throw my money to mechanics.

[detjoe]

Hey BUgsdad: you seem sto have a ton of info about auto trans, how/what do you feel is necessary about the sss shift kit, good, bad, unnecessary parts, better parts for durability, you know you sh*t and I enjoy your descriptions about the parts and their design vs. their proposed function and how they work together...Just telling me what parts to get is ok, but being able to explane each part and why it is better, now that is cool.

 

it goes to the point of who works on your truck, if you do, you care. and you care about the parts and how/why they work so much better.

 

After smoking a reg SSS and you pull off to talk...he asks why your truck is quicker and you know exactly why, and the guy who asked has NO idea what you are talking about

 

I agree if it is yours and you have know how, do it.

 

thanks for sharing your info (experence )

[zippy]

that reminds me of the guys that have the kenne bell supercharger telling people why intercoolers aren't neccessary, "because kenne bell says so". my doctor can explain arthritis to me, doesn't mean i know enough about it to try to explain it to someone else.

[Bugsdad]

you seem sto have a ton of info about auto trans, how/what do you feel is necessary about the sss shift kit, good, bad, unnecessary parts, better parts for durability, you know you sh*t and I enjoy your descriptions about the parts and their design vs. their proposed function and how they work together

<{POST_SNAPBACK}>

 

I don't know the contents of the sss shift kit so I won't comment on it. I won't guess at stuff based on what I've heard from someone else. I have personal knowledge of the servos that were in question and I'm familiar with getting bad work from mechanics that shouldn't be servicing lawn mowers let alone vehicles. I already inadvertently stepped on the toes of established people on this board so I definitely won't start getting involved in what isn't necessary or good about another's shift kit.

I'm glad you saw something you liked in the other post on the 4L80E. I try to help where I can but I'm not lucky enough to own an SS and really just stopped by to help with the issue of the 4L80E.