Help....what's the DIFF

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

CookieJR

CookieJR

10 Year 15 Year
Joined
Mar 18, 2008
Threads
26
Messages
107
Location
kelowna
Real time help needed.
My crown gear is busted in my front diff so I bought a pumpkin out of the paper.
I got both of them on the floor and discovered they are not the same. The one I bought is from a non-ADD truck.

Can I make this work by taking some of the components out of my ADD diff and putting them into the one I bought? ........or should I be looking for another Diff? I am looking for the easiest way to get her back in the woods.

I took some pics that I will post up laterr
 
yes. just unbolt your ADD stuff and put it on the other 3rd member. I've done the reverse of what you are doing to convert to manual hubs and it worked fine.
 
If you have manual hubs installed now (highly recommended), you're better off installing the non-ADD diff and plugging the vacuum lines, or even tearing out all the vacuum and electrical crap.
 
toyminator said:
yes. just unbolt your ADD stuff and put it on the other 3rd member. I've done the reverse of what you are doing to convert to manual hubs and it worked fine.
Click to expand...

So it will become clear when we take the diff cover off and remove the ADD shaft/thingamajig from the driverside of the third member.......and it will bolt into the non ADD diff. Is there a horse-shoe clip holding the ADD shaft in there?

The boy (my son) just wants to get his 4X working and plans on a SAS in the future.
 
MARLIN375 said:
So it will become clear when we take the diff cover off and remove the ADD shaft/thingamajig from the driverside of the third member.......and it will bolt into the non ADD diff. Is there a horse-shoe clip holding the ADD shaft in there?

The boy (my son) just wants to get his 4X working and plans on a SAS in the future.
Click to expand...

You don't even have to unbolt the diff cover. just unbolt the shaft on the side. 6 bolts I think.
 
Ah........ I don't think we are talking about the same thing.

The ADD diff. has a short shaft that is flush with the outside of the case (where the ADD gears engage when activated).

The non ADD diff has the standard spline-in (spider gear) that the axle shaft fits in, or some kind of short axle in place of the ADD unit.

CookieJR is going to post up a couple of pics shortly.

On my FJ40 I could take the pinion shaft out with out removing the carrier from the housing. How do I get the axle stubs out on this thing without having to take the crown out?
 
pics

pictures
4234.webp
34.webp
fsdf.webp
 
toyminator said:
yes. just unbolt your ADD stuff and put it on the other 3rd member. I've done the reverse of what you are doing to convert to manual hubs and it worked fine.
Click to expand...

As already posted it is an easy process to switch betwixt ADD and non ADD by swapping tubes. And again as already posted I would throw the non ADD setup in there and get a set of manual hubs.

A IFS front diff is something one should not pay more than a 6 pack for though, I have at least one sitting outside in the scrap pile that you would have been welcome to...

IFS_diff2.jpg
 
There is something very strange goin on here.

Look at the shaft sticking out of our ADD tube compared to yours.
The first pic is the side of the pumpkin after taking the ADD tube off.
 
Another new development...... the original crown gear has 4.6 stamped on the edge.

The (older) $20 replacement has 4.1 stamped on it.

And we thought they all came with 4:10s.

I think Mr T was having a bit of fun putting some experimental/prototype parts into this truck????? could this be transforming into a Tacoma.

Edit: We remember the PO saying something about this truck coming with the "Big Wheel Kit" from Toyota that may explain the 4.56:1 gears.

Another question......do we keep the 4.56 gears or go with 4.10.......cross referencing what was built over the years it is not looking good for the SAS with 4.56 gears?
 
Last edited:
the lower the gears the better.
4Crawler.com main page has tons of info on toyotas including what color paint toyota used to paint the end of the pinion. different colors represented different ratios. 4.10 is pink
 
2ndGenToyotaFan said:
You have to have the same gear ratio front and rear, or you won't go far in 4wd. The drive train will bind up....
Click to expand...

Yes....aware of that, thanks. Just adding another twist to the story.



WristPin said:
the lower the gears the better.
4Crawler.com main page has tons of info on toyotas including what color paint toyota used to paint the end of the pinion. different colors represented different ratios. 4.10 is pink
Click to expand...

At the end of the day, the decision has been made to SAS this truck:clap:. It is currently a light weight 2wd:hillbilly:.

I was looking at another site (Trailgear.com) they had a table of Toyotas produced and years with diff ratios. The 4.56 (that is in the rear of CookieJR's truck) was not available in the "solid axle" years, so we have to find an after market 4.56 to throw into the SAS conversion. The 4.56s that are in there seem to turn his 33s without any trouble.
 
:clap:
 
2ndGenToyotaFan said:
The solid front axle diffs are the same as the rear axle diffs, so if you can find another 4.56 8in diff, throw it in the front!
Click to expand...

You mean the rear axle 4.56 diff from his 95 will likely fit in a 85 solid front axle? So we need to find any wrecked truck with a 4.56 rear end..thats a more affordable field.

Are 4.56 ratios (crown & pinions) available for the older solid axles?

Thanks for the info.
 
Yes there are after market 4.56 gears available for the 8 inch diffs. FYI the V6 rear diffs are a little stronger design, but will still fit the front axle, or if you don't have the V6 diff in the rear already, swap a V6 diff into the rear, then put your rear upfront... If that makes sense... :D
 
welding

i have an old 4.10 non add ifs diff sitting around and i was wondering if i could take the carrier out and weld it and install it into a v6 rear axle off an 89 pu with 4.10s will it work??
 
CookieJR said:
i have an old 4.10 non add ifs diff sitting around and i was wondering if i could take the carrier out and weld it and install it into a v6 rear axle off an 89 pu with 4.10s will it work??
Click to expand...

NOPE.

Wait... do you mean a FRONT IFS diff? That's what I assume you meant.
 
You must log in or register to reply here.

Share this page

Back
Top Bottom