Questions for Ls1 swap guys - The 1947 - Present Chevrolet & GMC Truck Message Board Network

GMCRob · 09-28-2008, 03:38 PM

I just finished up a LS1 swap in a 71 chevy truck and everything was working perfect exept my tranny wouldnt shift if you got on it hard, it would shift fine driving normal. well at the time my computer wasnt tuned yet so i figured it was that, Then the tranny went out so i put another one in it and took my computer to a guy and had my gear ratio and tire size changed and took all of the stuff i didnt need out. Well it is still doing the same thing, I am afraid of burning another tranny up. What else could it be, some kinda sensor or something , my computer is not throwing any codes, and the guy that did my computer does all the cars around here so i know hes good. Any kinda help would be great Thanks.

**LEEVON** · 09-28-2008, 04:44 PM

what tranny are you running? 4l60e or 700R4?

GMCRob · 09-28-2008, 04:49 PM

Sorry about that im running the 4L60E,

jkade · 09-28-2008, 05:03 PM

Call Jesse @
www.wait4meperformance.com and tell him what it is doing. Sounds like the speed sensor may not be acting right, but I am just guessing.

68 short step · 09-28-2008, 08:25 PM

you did hook up the TCC wire right???? its the purple one that goes to the brake switch...
also you have the BEST tuner local to ya, in warr acres, his name is glen (hope he is the one you are useing)....

Ackattack · 09-28-2008, 08:45 PM

might be a question the guys over on the "Hybrid" forum on LS1tech can help you with. Lot more guys over there to pool from. One of them may have had the same issue.

Good luck!

GMCRob · 09-29-2008, 05:58 PM

Yeh glen is the guy i am using, and yes i hooked up the brake light switch. I took it out today and drove it a little and its not that it doesnt shift, it actually gets to about 5500 RPM and the tranny just freespins, kinda like it throws itself into nuetral. but only at wide open, just cruisin it does fine

68 short step · 09-29-2008, 06:03 PM

those sound ezactly like the symtoms of the TCC wire not hooked up, what year engine/trans are you useing? also whats it out of?

GMCRob · 09-29-2008, 06:11 PM

It is out of a 2000 SS camero, i am running a street and performance harness, I had a buddy put it on a scanner and it said my converter is locking up. That is the brake switch deal your talking about right

68 short step · 09-29-2008, 06:16 PM

yea, thats what it controls, the lock-up of the converter.....any mil lights??? also did you install a cam??

GMCRob · 09-29-2008, 06:20 PM

its a bone stock engine, the only codes is a front o2 sensor,

68 short step · 09-29-2008, 06:25 PM

hmmmm, my suggestion is to take it to glen, and have him ride along with you and he can monitor the eng/trans live and see whats going on.....

jkade · 09-29-2008, 08:31 PM

Quote:

Originally Posted by GMCRob

Yeh glen is the guy i am using, and yes i hooked up the brake light switch. I took it out today and drove it a little and its not that it doesnt shift, it actually gets to about 5500 RPM and the tranny just freespins, kinda like it throws itself into nuetral. but only at wide open, just cruisin it does fine

Nevermind the speed sensor then, let us know what you find out.

drman929 · 09-29-2008, 11:49 PM

I don't know if it's the same on the cars, but on my 05 truck engine, I had to run a power wire to the transmission. It is part of circuit 1020 of my factory harness, so I just took that 1020 wire and ran it to a fused 10a pink hot lead and everything works fine. Something to think about?

The TCC is supposed to have 12v except for when stopping, so I used a 5-pin relay to switch the power from the TCC wire to the brake lights when I hit the switch.

09-28-2008, 03:38 PM	#1
GMCRob Registered User Join Date: Jan 2007 Location: moore, oklahoma Posts: 7	Questions for Ls1 swap guys I just finished up a LS1 swap in a 71 chevy truck and everything was working perfect exept my tranny wouldnt shift if you got on it hard, it would shift fine driving normal. well at the time my computer wasnt tuned yet so i figured it was that, Then the tranny went out so i put another one in it and took my computer to a guy and had my gear ratio and tire size changed and took all of the stuff i didnt need out. Well it is still doing the same thing, I am afraid of burning another tranny up. What else could it be, some kinda sensor or something , my computer is not throwing any codes, and the guy that did my computer does all the cars around here so i know hes good. Any kinda help would be great Thanks.

09-28-2008, 04:44 PM	#2
LEEVON Moderator Join Date: Jul 2006 Location: Ozark, MO Posts: 4,888	Re: Questions for Ls1 swap guys what tranny are you running? 4l60e or 700R4? __________________ '20 Silverado Trail Boss ~ '17 Tahoe ~ '79 K15 Sierra Grande ~ '76 Blazer 2wd ~ '71 Cheyenne swb ~ '55 Pontiac Safari ~'50 3100 bagged ~ '80 Wife ~ Late model kids

09-28-2008, 04:49 PM	#3
GMCRob Registered User Join Date: Jan 2007 Location: moore, oklahoma Posts: 7	Re: Questions for Ls1 swap guys Sorry about that im running the 4L60E,

09-28-2008, 05:03 PM	#4
jkade Senior Member Join Date: Nov 2005 Location: AL Posts: 2,519	Re: Questions for Ls1 swap guys Call Jesse @ www.wait4meperformance.com and tell him what it is doing. Sounds like the speed sensor may not be acting right, but I am just guessing.

09-28-2008, 08:25 PM	#5
68 short step Senior Member Join Date: Aug 2005 Location: tulsa OK Posts: 3,070	Re: Questions for Ls1 swap guys you did hook up the TCC wire right???? its the purple one that goes to the brake switch... also you have the BEST tuner local to ya, in warr acres, his name is glen (hope he is the one you are useing)....

09-28-2008, 08:45 PM	#6
Ackattack Senior Member Join Date: Aug 2002 Location: Valley Center KS Posts: 3,525	Re: Questions for Ls1 swap guys might be a question the guys over on the "Hybrid" forum on LS1tech can help you with. Lot more guys over there to pool from. One of them may have had the same issue. Good luck! __________________ Project Bruiser: 68 Pro-Touring C-10 5.3L / 4L60E Project Ironhide: 97 GMC Crew Cab 4x4 Cummins SOLD: '69 GMC 1/2T SWB TBI'd: Project No Buck Assembly Manual Index Sign up Thread!!! Factory Service Manual Index

09-29-2008, 05:58 PM	#7
GMCRob Registered User Join Date: Jan 2007 Location: moore, oklahoma Posts: 7	Re: Questions for Ls1 swap guys Yeh glen is the guy i am using, and yes i hooked up the brake light switch. I took it out today and drove it a little and its not that it doesnt shift, it actually gets to about 5500 RPM and the tranny just freespins, kinda like it throws itself into nuetral. but only at wide open, just cruisin it does fine

09-29-2008, 06:03 PM	#8
68 short step Senior Member Join Date: Aug 2005 Location: tulsa OK Posts: 3,070	Re: Questions for Ls1 swap guys those sound ezactly like the symtoms of the TCC wire not hooked up, what year engine/trans are you useing? also whats it out of?

09-29-2008, 06:11 PM	#9
GMCRob Registered User Join Date: Jan 2007 Location: moore, oklahoma Posts: 7	Re: Questions for Ls1 swap guys It is out of a 2000 SS camero, i am running a street and performance harness, I had a buddy put it on a scanner and it said my converter is locking up. That is the brake switch deal your talking about right

09-29-2008, 06:16 PM	#10
68 short step Senior Member Join Date: Aug 2005 Location: tulsa OK Posts: 3,070	Re: Questions for Ls1 swap guys yea, thats what it controls, the lock-up of the converter.....any mil lights??? also did you install a cam??

09-29-2008, 06:20 PM	#11
GMCRob Registered User Join Date: Jan 2007 Location: moore, oklahoma Posts: 7	Re: Questions for Ls1 swap guys its a bone stock engine, the only codes is a front o2 sensor,

09-29-2008, 06:25 PM	#12
68 short step Senior Member Join Date: Aug 2005 Location: tulsa OK Posts: 3,070	Re: Questions for Ls1 swap guys hmmmm, my suggestion is to take it to glen, and have him ride along with you and he can monitor the eng/trans live and see whats going on..... Last edited by 68 short step; 09-29-2008 at 06:25 PM.

09-29-2008, 11:49 PM	#14
drman929 Registered User Join Date: Nov 2006 Location: Arkansas Posts: 232	Re: Questions for Ls1 swap guys I don't know if it's the same on the cars, but on my 05 truck engine, I had to run a power wire to the transmission. It is part of circuit 1020 of my factory harness, so I just took that 1020 wire and ran it to a fused 10a pink hot lead and everything works fine. Something to think about? The TCC is supposed to have 12v except for when stopping, so I used a 5-pin relay to switch the power from the TCC wire to the brake lights when I hit the switch.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.