So just got back from running the whipsaw trail with a few friends and grenaded my rear end. I pulled the rear drive shaft and kept the center diff lock expecting that I would be able to drive out in front wheel drive however I got nothing but engine revs when I attempted to do so. Is there something weird about the GX and allowing it to function without a drive shaft that will allow it to be two-wheel drive rear (done this in the past with broken cvs) but not two wheel drive front? Another issue I have is now my transmission won't hold park and I get the A/T P light indicating (Transmission park malfunction) when it's in park and the rig just free rolls.
Grenade rear... But not able to drive out? (1 Viewer)
- Thread starter ebbs15
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- #3
I'm definitely sure if the rear but not sure it's not also the transmission.
I say definitely because I towed it out with transmission in neutral and tcase in neutral so neither spinning, and I could feel and hear the grinding, popping of the rear the whole way.
I'm hoping for f+r diffs or r+CV... But I rarely get what I hope for lol
Not trying to ambulance chase, but I do have a good 8" 3rd member sitting around (removed from my GX a couple months ago when I did a 8.2 upgrade). PM me if you have any interest in it, as I'd rather sell it to a forum member than eBay it.
Not sure breaking a CV AND grenading your rear diff counts as an easy fix but at least @ebbs15 knows what's broken now haha.
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- #11
Thanks but I'm ordering from ECGS a built third with 4.10s and a harrop. As well as a front open. It'll get me back to stock with my 34's.
You keeping the 8.0? If you are going through the effort of a re-gear and locker, I would strongly (no pun intended) advise an 8.2 swap instead with 4.56 gears (this is the highest aftermarket gearset offered for a 8.2). By far the best money I've ever spent on my GX. It rips with 4.56s and no change in MPG. And I don't have to worry about grenading the 8.0 any more.
You can pull a 8.2 from a 5th gen 4Runner and it will bolt right in. I bought a new OEM Toyota Aussie-spec housing with a factory truss, and got a core 8.2 3rd member from eBay for $300. Then I installed the ECGS 8.2 and re-used by OEM 8" axleshafts, springs, brakes, shocks, etc. It bolted right in, other than the rear sway bar which you do need to get form a 5th gen 4Runner. The core 8.2 then went back to ECGS.
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- #13
I want to, though I feel 4.56 is way over geared.( 4.10 is actually perfect for 34's and I've never felt I was under powered) per Gear Ratio Calculator - https://www.grimmjeeper.com/gears.html (pics are from there) .64 mph high at 80 with 4.10 on 34's vs 3.73 on stock.
But wife and I are also doing ivf so $ is tight. This may end up with me replacing gears again in a few years, but, I've got an FJ80 I'm building to take hardish stuff and the gx will move to daily driver duty.
Definitely thought long and hard about the 8.2 but it's about 2.5k more going through ECGS with the elocker. I know I could find one from the junk yard then follow your steps, but I'm trying to get this done in my driveway on jack stands with no experience lol so the simpler the better and honestly wouldn't know a good 8.2 from a bad.
As I said I might end up back in this same situation, but I'm hoping that off that's true it'll be a few years down the road and I'll be a little older and more experienced, and more to the point, have more $ in the car fund lol.
I certainly get the $$$ issues and have been there as well 
. But, from my experience, a GX is NOT over-geared with 4.56s, and I only have 33s on my rig. I also hemmed and hawed over the gear ratio, including making lots of tables, and was very worried that I'd be over geared.
Since re-gearing, I've put over 5,000 miles on on the rig - including commuting with it on the interstate, and towing our camper all of the way to MT. It's so much better to drive than it was with 3.73s, and it zips along at 2,700 rpm at 80 mph. Zero difference in MPG around town, towing, or on the interstate. MPG on 2-lane backroads may be 1 mpg or so less, but is such a minor difference that it's not noticeable. I'd suggest at least a 4.30 gear for your application, but think you would be very happy with 4.56 or even 4.88s given that you have 34s. The 2UZ-FE likes to rev and responds well to gearing.
. But, from my experience, a GX is NOT over-geared with 4.56s, and I only have 33s on my rig. I also hemmed and hawed over the gear ratio, including making lots of tables, and was very worried that I'd be over geared.Since re-gearing, I've put over 5,000 miles on on the rig - including commuting with it on the interstate, and towing our camper all of the way to MT. It's so much better to drive than it was with 3.73s, and it zips along at 2,700 rpm at 80 mph. Zero difference in MPG around town, towing, or on the interstate. MPG on 2-lane backroads may be 1 mpg or so less, but is such a minor difference that it's not noticeable. I'd suggest at least a 4.30 gear for your application, but think you would be very happy with 4.56 or even 4.88s given that you have 34s. The 2UZ-FE likes to rev and responds well to gearing.
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- #15
Thanks for the insight. I might have to think about it for a bit (got a trip coming up, now in the 80, so no urgency to get the order in). What's your speedometer read vs actual?I certainly get the $$$ issues and have been there as well
Since re-gearing, I've put over 5,000 miles on on the rig - including commuting with it on the interstate, and towing our camper all of the way to MT. It's so much better to drive than it was with 3.73s, and it zips along at 2,700 rpm at 80 mph. Zero difference in MPG around town, towing, or on the interstate. MPG on 2-lane backroads may be 1 mpg or so less, but is such a minor difference that it's not noticeable. I'd suggest at least a 4.30 gear for your application, but think you would be very happy with 4.56 or even 4.88s given that you have 34s. The 2UZ-FE likes to rev and responds well to gearing.
The speedometer is based on the wheel speed sensors, so it's unaffected by gearing (but is affected by tire size). I have a Heal-Tech speedometer calibrator spliced into my rig so it's dialed with 33s. The correction was around 7%. With 34s you are probably off by 8% or more.
In the long run it's probably cheaper to repair your 8" for now with a used 3rd member to get the rig back on the road. They are around $500-700 on eBay and may be higher or lower at a local salvage yard (I'll probably ask ~$500-600 for mine when I get around to eBaying it). You can easily swap the 3rd in your driveway in a day or less. The only other parts you will need will be a gasket or FIPG tube and some gear oil. Then, when you are financially able, you can do a proper 8.2 upgrade and reagear with locker(s), and resell your 8" parts for about what you paid for them.
