Awesome thanks for the insight. Just trying to learn about it. I’m not familiar with re gearing. If you do the diffs, do you have to do the front and rear? I don’t think you would, since I wouldn’t expect the transfer case to be locked at speeds that would make a difference. Reason I started down this rabbit hole, was just doing the rear axle/hub re fresh on my LC. Vehicle has 310k miles, I don’t have any vehicle history on it, I was figuring I’d be in the third members sooner rather than later for some reason I’d expect. Not sure how long those bearings and gears can last. I do plan on pulling it out to take a look.
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tmxmotorsports
SILVER Star
If you regear the rear the front must be done at the same time.
If you re-gear , solid pinion crush sleeves are a good idea.
Potentially dumb question. Looking for instant gratification rather than searching tonight.
Obd1 rig (94)
I just pulled my motor/trans this evening, along with the entire engine harness and ecu. Hoping to mount my gm ecu in the factory location. Here’s my dumb question - I don’t need to retain the Toyota ecu, right? I know I’ll be using some of the sensor wiring to retain gauge function, which got me a bit concerned about how much else I may have to retain…
Thanks in advance!
Obd1 rig (94)
I just pulled my motor/trans this evening, along with the entire engine harness and ecu. Hoping to mount my gm ecu in the factory location. Here’s my dumb question - I don’t need to retain the Toyota ecu, right? I know I’ll be using some of the sensor wiring to retain gauge function, which got me a bit concerned about how much else I may have to retain…
Thanks in advance!
You don’t need the ecu, Just a few wires and plugs from the harness.
thatcabledude
GOLD Star
I would leave the GM ECM under the hood. I have found it’s not worth the headache of trying to mount under the dash IMO
tmxmotorsports
SILVER Star
Correct it's also where they are in the donor vehicle
Not sure it “easily fits” behind the glove box. You should be able to get all the wires through by starting in the cab or de- pinning the ECM. Guess it’s a matter if you really want to or not. You don’t need to from a reliability point. It’s in the engine bay in GM vehicles. Which you probably know. If you do it, love to see how you mounted it. Good luck.
has anyone done a 4.8 in their 80 yet? I have a super low mileage one lined up and I think with a cam, mild tune and my 4.88 gears installed it would still be light years more power then the 312k mile tired motor that I have now. Thoughts or opinions from anyone is appreciated before i pull the trigger on the motor combo.
thatcabledude
GOLD Star
If that’s what I had and there were no readily available and decent 5.3s I wouldn’t hesitate to run it. Can always be easily swapped for more displacement if you wanted it later.
That was my thoughts as well. If it feels slightly underpowered, i could easily swap with a bigger motor down the road. My 1FE is just worn out at this point so I need to do something and this came up. Curious what gearing everyone runs after the swap though.
Depending on which trans you choose. 4speed auto 6 speed auto or manual. Tire diameter also make a difference.
On my 97 fzj80 swap I'm going with a gen4 6.0 (now a 6.9) , 6l80e with a 4.02 first gear an a .67 overdrive. I now have 4:56's an 37's. This ends up running 2200rpms @75 mph with the LS. Also gives me a crawl ratio with my 3.12 low gear set of 57:1.
In my opinion bigger displacement equals more torque at lower rpms. Torque at low rpm is a big deal in a 4x4. If your adding a cam to the 4.8 that immediately adds 1000 dollars to a swap. 500 for the cam/springs, 250-500 for a dyno tune. In my opinion you may as well use that 1000 to get a 6.0 instead. A cam is only going to add significant power over 3000rpm.
I think your absolutely right the more i research about cams for the 4.8s. They only add power way up high which this isnt going to be a race car. I need torque more then anything. I am going to hold out for a 6.0. I appreciate the help guys.
I think you could find a good running 6.0 for around 1200-1500. I've seen them for 900 here n there. Higher mileage ones if on a budget I think are fine too but I would consider having a machine shop hone the bores. Then install fresh quality rings on the old original pistons. Very inexpensive way to freshen up the motor and should get a lot of miles out of it.
I had a 4.8 2000 silverado 1500. 5 speed manual trans. Never needed more power. Towing 20ft bay boat etc. it’ll be great if you have it. Watch some of Richard Holdeners videos on the “4.great “ engine series. It’ll be good to go. Especially if it’s a clean runner already. Literally do nothing to it and put it in.
Should be fantastic
Little teaser.
Gotta get the lift on to measure the driveshafts. So even though it feels like I’m not to that stage yet, I want to get the drive shafts cooking. While I finish up other items.
