Registry 8x Series V8 Swaps (12 Viewers)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

I’m also working with the trail blazer shift cable 15785087. I think it’s still way too long, looping it back from the shifter on the passenger side over the t-case then fwd again. It loops all the way back over the gas tank. You could easily take 2 ft out of it. Not sure if you can cut or adjust these or not. Or did you leave a coil in it?
For the tcase shifter I’ll have to take a picture of the bracket with some measurements. I have a 96 so ended up scrapping the provided marks part and fabricating a whole new plate. I only had to adjust the rod out a half turn or so.
The trail blazer cable is very long, ThatCableDude had a good sketch earlier on how he snakes it in an S formation over the transmission.
I haven’t finished this section yet but plan to place the transmission lever facing up, modify the cable holder on the trans side to hold it up and point it down towards the lever with a slight angle. Do 1 180 over the tcase, run the cable up the transmission towards the engine, do another 180 turn and then mount the shift handle side to the passenger side transmission tunnel with a bracket.
 
Hey! It’s been a minute since I’ve posted on this thread but I really need some help here. I’ve been having alternator issues for a while and my 80s voltage goes far too high.

I don’t think my alternator (a Chevy 350 alternator) is hooked up correctly. I think the issue lies in the tickler wire/voltage sensing wire not being hooked up in the right spot on the Toyota harness. If anyone has a 1992 LandCruiser and knows which wire is the tickler I’d really appreciate it.

The Toyota harness has a white wire, black and white wire, blue and white wire , and yellow wire. I know the white wire is power and the yellow goes to the charge light. Other than that I could have something hooked up incorrectly.
Thank you!
 
Last edited:
It’s not super fresh in my head but in my ‘92 I wired one wire to the voltage meter circuit and the other 3 that came off my 4pin alternator are not required(I may be misremembering this, but I think that’s correct). The bat(+) obviously an additional connection.

It sounds like a voltage regulation problem to me, is your dash voltage meter hooked up? Is it reading a steady output? IIRC it should put out around 14.4v if not being controlled by the Gm ecu?

Edit: pretty sure the yellow is the input for the voltmeter circuit. The white(10?awg) is you main power(battery+) connection. I reorganized mine to send the bat+ feed through a fuse block on the way to the battery. I moved my primary battery to the driver’s side(US) and reorganized most of the harness in that zone to accommodate cleanly.

Hey! It’s been a minute since I’ve posted on this thread but I really need some help here. I’ve been having alternator issues for a while and my 80s voltage goes far too high.
I don’t think my alternator (a Chevy 350 alternator) is hooked up correctly. I think the issue lies in the tickler wire/voltage sensing wire not being hooked up in the right spot on the Toyota harness. If anyone has a 1992 LandCruiser and knows which wire is the tickler I’d really appreciate it.

The Toyota harness has a white wire, black and white wire, blue and white wire , and yellow wire. I know the white wire is power and the yellow goes to the charge light. Other than that I could have something hooked up incorrectly.
Thank you!
 
Last edited:
It sounds like a voltage regulation problem to me, is your dash voltage meter hooked up? Is it reading a steady output? IIRC it should put out around 14.4v if not being controlled by the Gm ecu?

Edit: pretty sure the yellow is the input for the voltmeter circuit. The white(10?awg) is you main power(battery+) connection. I reorganized mine to send the bat+ feed through a fuse block on the way to the battery. I moved my primary battery to the driver’s side(US) and reorganized most of the harness in that zone to accommodate cleanly.

Hey! It’s been a minute since I’ve posted on this thread but I really need some help here. I’ve been having alternator issues for a while and my 80s voltage goes far too high.
thank you for the input, I have a kind of different set up than most people with v8 swaps is definitely what I’ve gathered from this thread lol

I’ll double check my wiring and look into getting a fuse that goes to the battery (I really should have done that in the beginning looking back).

I was able to maintain the entirety of the stock Toyota harness and ECU and my Chevy 350 doesn’t have an ECU. I am running a Holley Sniper EFI system which doesn’t regulate voltage, so the only way would be through the Toyota ECU. I know for a fact my alternator has an internal regulator so that only leaves wiring as an issue if I’m not mistaken.

Ive gone through multiple alternators trying to figure this issue out and they all have the same issue of higher than normal voltage.

I am also wondering if that yellow wire for the charge light is the tickler wire, since I’ve heard about it being just that. But I also have another 80 swapped with a TBI Chevy 350 which doesn’t have this problem I should look at that too, but even it has some funky stuff going on.
My gauge itself is hooked up but the light isn’t, I have the yellow wire going to that light capped off btw

I’ll update with what I find later today…
 
thank you for the input, I have a kind of different set up than most people with v8 swaps is definitely what I’ve gathered from this thread lol

I’ll double check my wiring and look into getting a fuse that goes to the battery (I really should have done that in the beginning looking back).

I was able to maintain the entirety of the stock Toyota harness and ECU and my Chevy 350 doesn’t have an ECU. I am running a Holley Sniper EFI system which doesn’t regulate voltage, so the only way would be through the Toyota ECU. I know for a fact my alternator has an internal regulator so that only leaves wiring as an issue if I’m not mistaken.

Ive gone through multiple alternators trying to figure this issue out and they all have the same issue of higher than normal voltage.

I am also wondering if that yellow wire for the charge light is the tickler wire, since I’ve heard about it being just that. But I also have another 80 swapped with a TBI Chevy 350 which doesn’t have this problem I should look at that too, but even it has some funky stuff going on.
My gauge itself is hooked up but the light isn’t, I have the yellow wire going to that light capped off btw

I’ll update with what I find later today…
Okay, so I’ve done some digging into my 80 only to discover that my sensing (on/off or the wire that’s supposed to go to a dummy light) wire from my GM alternator isn’t going to anything. This has to be what’s causing my issues, right?

I’m still stumped as to which wire it should go to on the Toyota harness though…

Edit: What I think I will end up doing is looping the terminal 2 wire to the nut on the back of the GM alternator, this is so it senses voltage. I will hook up the sensing wire to the dummy light on the dash, that’s the yellow wire on the Toyota harness. This is so the alternator senses when the key is on and when it is off.
 
Last edited:
Okay, so I’ve done some digging into my 80 only to discover that my sensing (on/off or the wire that’s supposed to go to a dummy light) wire from my GM alternator isn’t going to anything. This has to be what’s causing my issues, right?

I’m still stumped as to which wire it should go to on the Toyota harness though…

Edit: What I think I will end up doing is looping the terminal 2 wire to the nut on the back of the GM alternator, this is so it senses voltage. I will hook up the sensing wire to the dummy light on the dash, that’s the yellow wire on the Toyota harness. This is so the alternator senses when the key is on and when it is off.
Do you have a 470 ohm resistor wired in anywhere? That’s typically needed for that old style Alt to work right. In place of the “charging” light.
 
Do you have a 470 ohm resistor wired in anywhere? That’s typically needed for that old style Alt to work right. In place of the “charging” light.
This is along the lines of what was wrong! Thank you for reminding me of this, I ended up disconnecting the sensor wire on the GM alternator after finding it made the voltage drop to 12.5v at 2000rpm. I removed it, leaving only the power wire to the Toyota harness and looped the tickler/voltage sensing wire to the post on the back of the alternator. So far this has solved my issue! Thanks for the help everyone!
 
I do have a question on gears, its something Im not very familiar with at all. I DO NOT want to start a p*** contest about doing the t-case vs diffs. More of a general question, does installing a GM trans, 4L80 in my situation, make the whole, you "should" re-gear with putting 35s (315s) or larger tires. I do plan on putting 315s on with a 3"inch lift. Has anyone done the homework on this? Ive read a lot of the stock FJ80 threads, just curious how the GM trans throws a curve to it. Thanks for any info.
 
I do have a question on gears, its something Im not very familiar with at all. I DO NOT want to start a p*** contest about doing the t-case vs diffs. More of a general question, does installing a GM trans, 4L80 in my situation, make the whole, you "should" re-gear with putting 35s (315s) or larger tires. I do plan on putting 315s on with a 3"inch lift. Has anyone done the homework on this? Ive read a lot of the stock FJ80 threads, just curious how the GM trans throws a curve to it. Thanks for any info.

I've read and re-read your post a few times and cannot figure out what the question is. Might want to re-phrase or decipher or something.
 
My question is. For the standard FJ80 set up with 35 inch tires or larger, conventional wisdom is to either re gear the diffs or the t-case so you can keep the engine in the power band better and not make the transmission hunt around for gears. Does the installation of GM trans change this equation at all, I’m assuming the gears inside are different than the stock Toyota trans. My initial statement of not getting into a debate over to do the diffs or t case gears was there are some older threads with people arguing about which to do, while both agreeing you need to re-gear.
 
I've had a couple GM trucks with the 4l80e and 1st gear is taller than other autos. If you're gears are on the tall side it takes an uncomfortable amount of throttle to get going.
 
Why not finish the swap and see how you like it first? Gears are easy enough to address even after the swap is completed. Just my $.02...
This you are repowering the 80 with a bigger engine the 4l80e does have a taller 1st gear.. just run it and see how it reacts it probably fine . I've done a 84fj60 with 6.0 4l80e with factory gears not 410 ratio on 33s was fine. You could ask guys who have done the sesp what tire size they have might get more of a response.
Tommy
 
I’m working through the HI/LO bracket issue now and shift cable, it’s all I have left to do. Been under the truck most of the day trying to get the hi/lo shifter in place. Did anyone modify the length of the transfer case shifter rod or just mess with the position of the shifter? I’ve got it in place, need to put the console trim back on to make sure it’s not hitting anything.
I added 1" to the rod on mine. Sadly I am back at working on the wiring and cleaning that up. I have hte ECU mounted and the fuse box should go back in today. Then I have to figure out what is wrong with my trans. Its the only thing not rebuilt on the drive train and I really don't want to pay for a 6L90 to be rebuilt.

Also I put an EasyGuard remote start & Keyless entry system in. Well...I am putting it in. Still trying to work out the kinks on the diodes to get the system to work correctly.
 
My question is. For the standard FJ80 set up with 35 inch tires or larger, conventional wisdom is to either re gear the diffs or the t-case so you can keep the engine in the power band better and not make the transmission hunt around for gears. Does the installation of GM trans change this equation at all, I’m assuming the gears inside are different than the stock Toyota trans. My initial statement of not getting into a debate over to do the diffs or t case gears was there are some older threads with people arguing about which to do, while both agreeing you need to re-gear.

If you look at the trucks the donor engine came from, most of them have much higher axle ratios (numerically lower) than the 80. So, for instance, an early 00's Silverado might have 3.23 gears or 3.42 gears. I think in some cases 3.73. So in effect, by plunking the same engine and transmission into an 80 with 4.10 gear ratio, you just "re-geared" already :)
 
If you look at the trucks the donor engine came from, most of them have much higher axle ratios (numerically lower) than the 80. So, for instance, an early 00's Silverado might have 3.23 gears or 3.42 gears. I think in some cases 3.73. So in effect, by plunking the same engine and transmission into an 80 with 4.10 gear ratio, you just "re-geared" already :)

Your typical 2500HD Silverado with 6.0/4l80e has 3.73 gears and a tire around 33" tall. Effectively the same ratio is an 80 with stock gearing and 35's.

I find that gearing is fine empty in the 2500HD, but it doesn't feel good towing anything. Starting on an uphill with a trailer seems much harder than it should be.

Conversely, the same 2500HD with a Duramax/Allison 1000 feels pretty happy with 3.73's and 37" tires towing anything.
 
I am running 37s on LS3 mated to a 6l80e with transfer case regeared both high and low gears. 10% under drive and 3.? Marlin low gears. Both diffs are are 4.56. No issues and like setup. Not much hunting gears on hills. BTW my regear was done prior to repower.
 

Users who are viewing this thread

Back
Top Bottom