How to: Deleting ADD system

Thank you!

With it off the truck, I'm going to see if I can rig it up to my press. I've never had good luck driving seals in with a hammer. They always seem to go in crooked, which is fine if they've got a shoulder to seat against, but I know these diffs don't.

 

Yes i have it saved as a favorite on my phone haha. Its 5.5mm

 

I am selling a diff tube without ADD. Im not sure if you would need to replace the internal parts though (i bought a whole diff and tube, that already had the internal parts that i needed). You definitely just need the shorter bolts and a new seal.

let me know if you're interested

 

I'm definitely stuck on this. No crawl box but I did the manual transfer case swap for reliability (less stuff to break) so silly to still be running ADD.

That said, this has become our road trip rig and the fuel economy already sucks as it's built out so worried I'd lose another % or two deleting the ADD (again, silly. But I'm a cheap bastard when it comes to buying fuel. Happy to buy truck mods, pony up for name brand Toyota parts, or spend money on a nice dinner every now and then but I hate buying fuel). So here I am.

Thanks! If I end up removing the ADD, I'll likely just order new. I've been watching and am stoked on your progress, though!

 

my new one comes today. Im planning on putting it in on Saturday. Shouldnt be too bad, minus changing the diff fluid and popping off the collar part that is in the diff.

Last part to my puzzle! Oh, and the prerunner selector cover for the interior is $22. So Ill be waiting on that.

 

Wouldn't happen to have the part number for that PreRunner selector cover by chance? I have all the parts for the tube and a twin stick FJ converted on the shelf. I am going to try and knock all this out at once. I have some new parts in development for testing and need to get this part setup first. More to follow...

 

For some reason, I thought you had an Eco crawler. Anywho, the only reason I can see for keeping the ADD is either deep gearing causing vibes, or wanting 2L capability. Since you have twin sticks (I think?), you already have that and 4.30 gearing won’t be deep enough to vibe. I had 5.29s and had some minor vibes around 80+, so I went back to the ADD for now. I may change the gearing back up eventually.

For the week of having the ADD gone, I noticed maybe 0.3-0.4 mpg difference, and that’s what 5.29s spinning the shaft up 23% more than 4.30s would. I doubt you’ll see much, if any loss at all. I think the miniscule amount of
fuel saved vs things always working and spinning is worth the trade off, to me anyways.

 

This is good food for thought. The more I type things out and think about it, the more I realize now is the time to do this.

Thanks for all info @BLtheP and @fatfurious2

 

At 10% gear reduction over stock, assuming you're not running giant tires and a half ton of armor, it should feel better.

 

I have 4.56 gearing, and no vibes that I can feel. Lets hope I dont get any with the FJ tube, but it should be solid

 

What size tire?

 

285/75/16

 

You’ll be fine. I run 32’s on 5.29. Pushing 4500 driveshaft rpm when vibes start. I think it’s just the angles between the front diff and transfer case not being 100% perfect for high speeds. With the drivetrain angled down, that angles the tcase output up, and it’s higher than the diff which makes things a bit weird. What I experienced was an extremely minor hum at those high speeds. It was enough to bother me
though.

 

I think im going to wait for a bit on this. I hate being in a time crunch for this type of stuff.

I have all the parts, just not enough daylight. Im also weather dependent because I don't have garage space

 

This tool is now available. I don’t even need one right now but I ordered it….

 

This is the way

 

For anyone still doing this, this diff tube is the same as the FJ (without add) and then you can also sell the front diff to ECGS as a core for $125 and they will pay for shipping (exactly what I did from an ebay part)

https://www.tacomaworld.com/threads/gta-ontario-2005-toyota-4runner-for-parts.844235/

 

I may be revisiting this soon. I decided to try another OEM front driveshaft and noticed no vibes at 100 mph, whereas I had vibes at 85 mph on the stock shaft….there was some grease residue oozing out of the u-joints (stock non greasable), so there was a chance that they went somewhat bad from all the sitting there doing nothing the stock driveshaft does….then you go to spin the shaft with the ADD gone and it doesn’t like it.

I did attempt to change the stock u-joints but that didn’t go so well as I got impatient when they wouldn’t budge, and then they finally went and the u-joint cross dinged up the insides of the yokes.

So, bought a new shaft which seems all good. I may be getting rid of the ADD after all with potentially a manual t-case in the future. With the new transmission, I really don’t need 2L. And I’d still probably eventually get that anyways if I twin sticked the case, which maybe would be in the plans. Hmmmm.