So I have a 1989 2wd yota with a 4 spd manual transmission. I have larger tires on it right now and it seems kinda sluggish. So my plan it to a different set of gears in the rear. First though, I want to figure out what my gearing is now. I used this web site to determine the gearing that I have. http://www.off-road.com/trucks4x4/ar....jsp?id=274535 I checked my door sticker and this is what it said: C/TR 8D8/LA81 A/TM G662/G40. I know that the number that i have to pay attention to are G662. After comparing that on the gearing chart it reads that my truck has 3.071 gears in that back. This does not sound right to me. I thought I would have 3.73 gears or 3.90 gears. Help would be greatly appreaciated!

 

3.07 is the correct ratio.

The reason they installed the 3.07 was becase you only had 4 gears in the trans, so you need a higher gear ratio.

 

Thanks DeathCougar. I am actually thinking of swapping out the entire axle for a junkyard 4x4 rear axle with 4.10 gearing (which i Believe is pretty common). I think that this would be a lot easier for me than trying to change the gearing myself or paying a shop to do it. As is stands right now with 3.07 gearing my RPM's at 60mph is 2,050 which is kind of low...not much passing power. If i were to change to 4.10 gearing my RPM's would be at 2,737 according to my calculation which isn't horribly high.

Finally another reason that i was to change the gearing is so i can idle slower in first gear out on the trails since i do not have transfer-case with my 2wd LOL!

 

You won't have to swap the whole axle assy, just swap out the third member. Its all bolt in stuff, and you can find them at local wrecking yards.

 

Unless your 2WD truck is one ton it probably has the smaller 7 1/2 " rear and the 4X4 axle will be the 8" rear. It won't fit. Swapping the whole axle is easy you just have to weld the spring perches on the bottom of the axle, but you will have 6 lugs on the back and five on the front.

 

Yea, just swap the third member out, alot easier and will only take a couple of hours to do.

 

According to the differential chart from my first post, my third member is an 8.0", so it would fix most of the 4X4 third members. Also does anyone have an idea on how much these things cost at a junkyard?

 

... ask DeathCougar

 

The U-pull it junkyards around Portland sell complete rear ends for $115, thirds are cheaper.
On craigslist I have seen thirds anywhere from $50-350.
You can get a new/rebuild third from somewhere like Jaws Gear or East Coast Gear for around $400,
Shipping on a third is running about $65-75.

 

Are there any threads out there that show how to swap out a third member?

 

www.gearinstalls.com

its easy... undo the 4 bolts holding your driveshaft on...
take off wheels and tires... unbolt the backing plate/axle (4 bolts) from the axle tube...
slide axles all the way out... unbolt 8 bolts holding the 3rd member to the pumpkin...
apply blue RTV to the new 3rd after cleaning the mating surface...
place dif in axle and finger tight the bolts... have a beer or 6 (wait 1/2 hour) torque the bolts down good and tight... reinsert the axles being careful not to ruin the inner seals...
bolt axles back on... bleed the brakes... replace wheels... reinstall driveshaft bolts with blue loctite... drive away...

shouldnt take more than an hour and a half...

 

Another thing i just thought of, would i run into any problems in replacing my 2wd 3rd with one from a 4x4. For example, would the splines on my 2wd's axles fit into the splines in the new 3rd?

 

Yea man search around craigslist, that is most likely your best bet..

Or

Pm deathcougar and see what he has...


I had a 4cyl diff with 4.10's on craiglist for $40 and nobody wanted it.. So i decided to weld it up and keep it as a trail spare...

 

I found a guy that has an axle that came out of a 1987 4runner 4x4 22R. Would I be able to take that 3rd member and swap it out with mine. My concern is that his 4runner is a 1987 and my truck is a 1989.

 

i made a thread a while ago

 

You can use any 8.0" diff in the right ratio. If you are looking for 4.10s, then you should be able to pick one up for around $50. Doesn't matter whether it came out of a PU or 4Runner. The swap takes and afternoon at a slow pace.

https://www.yotatech.com/forums/f129...nstall-163698/

 

Thanks MATT16, I have seen your post on the 3rd member install before. Its pretty good.

The guy that I am thinking about getting the axle from is only selling as a full axle, not just the 3rd member. He is asking for 150 dollars for the whole rear axle. Would this be too much?