I just purchased a ls3 crate motor for my 56 Bel Air. I also have a 4L60E tranny. I have also purchased the GM controller kit. My question is will the controller also control the tranny?

 

whats the part number of the controller kit?

Thanks

 

The GM LS3 controller will not control the 4L60 tranny. 4L60 requires a stand along controller for it, that can communicate with the LS3 controller.

Now heres the kicker your 4L60 tranny as built will still not work with the GM LS3 controller even with correct stand along tranny controller. For the GM controller to work your tranny need to have ISS sensor. 4L70 tranny was first to have that sensor. I know all 2008 4LXX trannys have ISS sensors built in.

Your 4L60 most likely can be modified to add ISS sensor. Depending on who does work and when it's done, parts and labor adding sensor will range from $450 - $900 dollars.

How do I know this? The hard way and highest cost wise way. If I were you, I would contact John Spears @ Speartech (Forum Sponsor that builds custom wire harnesses) and seek his advice.

You could ask question in Auto Trans forum "Will 4L60 tranny work with GM LS3 engine controller" and see what responces are there. Hope all the tranny builders are up to speed on problem now.

 

I've been trying to get my 4L65E to work with my ls2 controller kit and a controller kit for the tranny as well. All from gmpp.

I haven't got it to work yet. Actually I fried my tranny after 1,5 miles of reasons im not sure of yet. It was missing a rpm signal, and the tps wires im not sure are hooked up right. The tranny is currently having the clutches replaced.

So my question is, whats an ISS sensor?

 

The GMPP LS engine controller kits are for the engine only. You will need the stand alone transmission controller kit to get any of the electronic shift transmissions to work. The GMPP trans controller is programmed on its own, seperate from the engine ECM.

Controllers & Accessories
12497316
Transmission Controller, 4L60-E, 4L65-E, 4L80-E
& 4L85-E Automatic
• Required when using a GM electronically controlled
automatic transmission
• Includes wiring harness, software and connector for
lap-top computer
• Controller allows full programming of shifting, as well as
part-throttle, wide-open throttle and shift firmness control
• Comes pre-programmed—simply enter rear tire diameter
and axle ratio
• Wiring harness P/N 124894 included

 

ISS sensor = Input Speed Sensor. The ISS was introduced in 2006 on the Trailblazer SS (4L70E). Then in 2007 it spread to a few more models and now in 2008 it's across the board on the 4L60E, 4L65E, and 4L70E transmissions.

My best guess is, unless your GMPP LS2 controller kit's supplied engine computer is latest and greatest one, lack of ISS sensor should not be a problem as engine controller did not need it to work.

My best guess is based on, GM doing an across the board incorporation of ISS sensor in 2008 4Lxx series transmissions. That indicates to me at least, that any 2008 LS2 engine application, along with LS3 application computers will be looking for input from ISS sensor.
I'm assuming GM was smart enough to have released their Controller kit for LS2 engine conversion with a engine management controller and transmission controller used prior to need for ISS input for both engine and transmission to work properly. That assumption is based on the potential number of customers that would be looking for Wiring kits to use with one are the other of abundance of used LS2 engines and used 4Lxx series transmissions out there in their conversion.

I would contact GM Tech support to see if their LS2 wiring kit supplied computers need ISS sensor input to work correctly.

 

OK guys, here is the response that I got. Give me a moment to format or post the picture.

We have not had any issue with using the GMPP Trans controller with the 4L transmissions - not sure what the reference to trans upgrade is all about. Our LS2 GTO has run our GMPP Engine control system and the current GMPP trans controller with a 4L trans without any issues. The only items that need to be considered are: (1) Use the TPS signal wires provided in the bulkhead connector of the engine harness for the trans controller TPS input, and (2) use the tach signal output in the same bulkhead connector for the RPM input - this will require a 5,000 ohm pull-up resistor (we have updated the instructions to include this recommendation as well)

More info - the guy talking about the ISS (input speed sensor ) upgrade is talking about using production-style TCMs, which is what Speartech uses. These would then require the the ISS.

The ISS is not used by any aftermarket TCMs, only the output speed which is available on the trans.

 

Robin,

Hope you don't take my post wrong. My hope is to clear up if there are other LS3 conversion kits out there like your LS2 kit so we all know our options to chose from and what works and doesn't work with GMPP kits as for 4Lxx trans needing ISS sensor to work properly.

Same goses for GMPP LS2 kits.


Based on the fact that the original poster with LS3 crate engine has already purchased GMPP controller kits, what is your take on if GMPP LS3 kit needs ISS signal or will work with just output speed?

Will it be a problem for people who might be thinking about purchasing one for LS3 application with 4lXX transmissions, if trans does not have ISS sensor?

Think that could be a problem that members should be aware of before they buy a GMPP LS3 kit for use with 4LXX series transmissions, not after.

I know I don't know the answer to that. I do know that the aftermarket Wire Harness kit I'll be using with my LS3 needs ISS input and will have working cruise control.

So, do GMPP Aftermarket engine and transmission controller and wiring kits work with LS3 with 4LXX series transmissions with or without ISS sensor and can you get them with cruise control capability?

Speartech LS2 wiring kits do not need 4LXX transmission with ISS sensor to work either, same as your aftermarket application. As for as I know that's true of all aftermarket LS2 wire harness kits.

Now, what about poster with LS2 and 4Lxx application that is already using GMPP LS2 Kit and has run into a problem.

Poster has a problem with his 4lxx transmission after conversion.

Do you think the wiring diagram you posted for GMPP kit was overlooked when he install his kit are maybe not included with kit he received from GMPP and this is cause of his problem?

From his post it sounds like he was missing rpm signal at one time, but that was corrected. I hope before he drove the car since it might have led to cause of frying clutches.

Or maybe just maybe that LS2 is putting out more HP&TQ than his trans is built to handle?

 

Poohousenext,
You making this way too complicated. If you buy any of the crate engine controllers and harness kits you must get a stand alone transmission controller and harness kit.

Not too hard. GM made the crate engines and controllers so you could use any trans you wanted for your street rod or hot rod. If you are using a crate engine as a replacement for a car that already has an electronic shift transmission and harness, use that or have it reworked and use a production PCM, not the pre-programmed crate ECM.

 

69LT1Bird,

I have too agree with you on my "You making this way too complicated." I've paid the price for people not looking before they leaped, by being the one assigned to fix leaper's problem.

This time I'm the one making the leap so I wanted to try and not hit to many problem I could have avoided if I had looked at things a little closer on the way to ground. I tend to read and re-read things which can also lead to as you said, make things to complicated.

The reason I backed away from the GMPP LS376/480 kit was I thougt GM was telling me up front they did not intend for it to be re-programmable, while others were telling me it was programmable/tunable. I knew I would need to be able to tune engine due to restrictive exhaust system I will have to use to start with an again when I could get custom headers built to flow it so I didn't want to fight that if indeed it turned out to be a problem that wasn't an easy work around.

When it came to GMPP transmission controller working with 4LXX series transmissions and LS3 crate engine too, I backed away from it, because when looking at buying a new crate 4L65 transmission to use with LS3 I found, with the exception of 4L85 an interesting statement in GMPP's description when I clicked on "Read More". I highlighted it in bold letters.

That statement made me decide against it too.

Do you think are know if GM left out LS3 engine due to it's output power or because controller or trans would not work with the GMPP LS3 engine controller, or as you said am I just making this way to complicated and trans controller will work with LS3 too?

I didn't know the answer so I decided to go the old fashion way and have custom harness made with controllers that worked with each other.

Only problem with that is I leaped before I looked and bought a built 4L65E assuming it would work, only to find out later that GM made change to LS 3 production engine controllers that required ISS sensor input for tranny to work properly. Had I speced the my conversion build to harness vendor before I bought it, I could have saved myself about $500.00 dollars by having parts installed when it was being built. Live and learn by taking my lumps...LOL

 

05-06 GTO's use the T42 stand alone controller also and they DID NOT have an input speed sensor installed in the transmission, although the Trailblazer/Envoys do.

I had a Chevy dealer flash the tranny controller with a bench harness. I used a GTO vin# off Ebay. It is fully tuneable with EFIlive. No problems.

 

Nice info..

Got the car running today.
Tranny works fine, but at WOT it downshifts as it's supposed to. But revs drops and increases making the rear end "jump" up and down. Very weird..

Anyone tried that?

 

Nevermind.. It works fine.

 

Robin, did that schematic for the bulkhead connector come from GMPP?
I bought my controller kit last winter and there was no drawing like that came with it.
Thanks
Bill

 

Of course it is You think that I could come up with that?

The schematic is included in the latest shipments.

Robin

 

i have a ? also concerning this thread. i have the ls3 crate engine with the gmpp ecm and harness with a built 4l60e. i also have the gmpp trans controller pn 12497316. here is my question. the trans controller needs a tps input with a 3 wire connector(red,white,black wires) Are all of these wires needed? tps is a 5v reference, a signal, and a ground. my bulkhead harness from my engine harness has the tps signal. are the other two wires needed or are they reduntant? same question for the rpm reference and the vss? the rpm reference is a two wire connection on my tcm(black/white) and my vss is a two wire(red/black). my bulkhead connector on my engine harness has the signal wires i need but i question the the other wires. how do you mate the two harnesses?