1982 pickup with Tacoma TRD rear axle?

[Sandman434]

Hello! I’m coming over from the 100 Series world but just bought a 1982 short bed pickup in an auction. It’s getting delivered in a couple days so I will have a better idea then of what things need to be replaced immediately and to get a project list together. Been reading through a lot of the threads on this forum since this is all new to me, and they have answered most of my initial questions, but a few more I’d like answered for a potential project!

I’m curious about what it takes to swap a complete 1st gen Tacoma TRD rear axle that has the factory locker. From what I have come across so far, they had the same 4.10 gear ratio as the front diff I’ll have, and the spring perches are the same width apart, so it should mount up in the same location. Here are the few questions I have not been able to get clarity on:

1. What modifications, if any, are required to the e-brake?
2. Are there any special considerations for swapping in an axle meant for ABS? Along with that, is the stock proportioning valve still used or bypassed?
3. Any other modifications that would have to be done to make it work

Additional note: I am interested in IFS hubs up front so I can run 4Runner calipers and rotors (located a set already machined down), and I pulled off a 4Runner master cylinder and brake booster at the local junkyard.

Hopefully I have not missed a whole thread that has answered all of this - if so, just point me in the right direction! Appreciate any advice or input from others who may have done the same.

 

[Devils Paw 80]

How did you discover the spring perches are the same width?
I was curious about the axle comparison and according to Google the entire axle width of the Tacoma is 60 inches while the ‘82 pickup has a rear axle width of 55 inches-for what that’s worth.

 

[pappy]

Additional note: I am interested in IFS hubs up front so I can run 4Runner calipers and rotors (located a set already machined down), and I pulled off a 4Runner master cylinder and brake booster at the local junkyard.

My thoughts on the front brakes. I would use your existing hubs, not IFS. Parts would be:

- FJ60 vented rotors
- 1990-95 V6 calipers. They have 4 large pistons.
- 1991-1995 4Runner V6 1" master cylinder. Get an AISIN/Advics master cylinder from Rockauto.
- 1990-95 V6 brake booster.

 

[Sandman434]

How did you discover the spring perches are the same width?
I was curious about the axle comparison and according to Google the entire axle width of the Tacoma is 60 inches while the ‘82 pickup has a rear axle width of 55 inches-for what that’s worth.

I feel like I saw it somewhere else in addition, but I found it on this old thread:

Are the Taco spring perches on the same centers as a '79?????

Also, how did you widen the front to match?

It bolted right in place of my IFS axle, so yes the spring perches are in the same spot. I did not widen the front with my IFS, but will be running the IFS hub bodies when I put the solid axle under it like I mentioned before.

 

[Sandman434]

My thoughts on the front brakes. I would use your existing hubs, not IFS. Parts would be:

- FJ60 vented rotors
- 1990-95 V6 calipers. They have 4 large pistons.
- 1991-1995 4Runner V6 1" master cylinder. Get an AISIN/Advics master cylinder from Rockauto.
- 1990-95 V6 brake booster.

View attachment 3924181

What would be your reasons for avoiding the IFS hubs?

 

[pappy]

What would be your reasons for avoiding the IFS hubs?

I guess my question would be "why do you want to use IFS" when you have perfectly acceptable hubs on the truck now? Maybe somebody else can chime in, but I don't see an advantage.

 

[Sandman434]

I guess my question would be "why do you want to use IFS" when you have perfectly acceptable hubs on the truck now? Maybe somebody else can chime in, but I don't see an advantage.

Not necessarily committed to it, but two main reasons - widening the track by a few inches (I have no interest in running spacers) and late model wheel options. From what I understand, any of the IFS 6-lug wheel cannot be used on the original hubs.

Side note - did you make or purchase that adapter harness for the master cylinder?

 

[gnob]

i like the ifs hubs for width, plus it makes the brake maintenance way more convenient.

yes. it also helps with wheel choices.

the og problem with ifs wheels on a sa front is the steering arm/tre contacts the wheel. this problem is lessened or avoided using hysteer.

 

[aztoyman]

I think where the confusion is coming from is the thread you quoted. The IFS (2nd Gen pickups) rear axle from 86- 94 or 95 is 3" wider than the original rear axle housing in your 82 which is a 1st gen pickup.

The 8" E-locker will still fit any of the housings but you will have to grind a notch and change a stud or something.

Guys that do a SAS on an 86- up IFS truck had to run 1 1/2" wheel spacers on the 85 and earlier straight front axles to match the width of the IFS rear axles. There is another option that is better than wheel spacers now but my point is that the 86- up rear axles are wider than the 85 and earlier.

Tacoma rear axles are even wider than the 86- 95 mini trucks.

The hubs being mentioned are not the"locking" hubs. @gnob is referring to the wheel hubs. They push the wheel mounting surface out and you don't need to run spacers to match the rear axle width. You can also upgrade to larger brakes with a slip on type rotor.

Locking hubs ARE different between the straight axle and IFS. If you're running the 85 straight axle, run the 85 locking hubs. There is a conversion kit to run IFS locking hubs on a straight axle but no need to if you have the correct ones.

 

[aztoyman]

There is a Toyota Bible 2.0 on Pirate 4x4 that should have all the info you need. I think there are other threads on Marlin Crawler and maybe Yotatech with all the axle widths and specs for swaps. Good luck with your new project!
Scott in AZ.

 

[aztoyman]

IDK what boosters and master cylinders fit the 1st gen trucks like yours. Since you're changing basically the entire braking system, you're most likely going to need to run an adjustable proportioning valve. Unless you find some kind of complete kit somewhere.

IDK how the rear drum parking brake is actuated in a 1st gen truck other than it is a cable. If your new rear axle has disc brakes ??? There are electric actuators out there to adapt.

As far as ABS, None of it will be operable so remove or don't use anything ABS. You'll have a pieced together system that you'll need to match components well enough that it will work properly and you can dial in.

You have a lot of choices in parts to sort through so confirm your choices before you start buying anything.

 

[BDSeff1fitty]

This link has a good overview of different Toyota axle widths that I've found useful as I've been playing around with what I want to do on the rear (full float conversion)

Toyota Axle Widths: 21 of 'em for Axle Swaps

The most Toyota axle widths you've ever seen: Specs and gotchas for minis, 4Runners, Tacos, T100s, and 40, 55, 60, and 80 Series Land Cruisers.

www.roundforge.com

E-locker diff will fit in your front and/or rear current housings. Going with a taco rear axle will make it ~2" wider in the rear than the front with IFS hubs.

If you modify the current housing, or a later IFS housing, it's very straight forward if you have a grinder, drill and tap. You can use the gasket as a template for the cut. Prior to drilling, I would then install the diff, and use the correct size center punch to mark your spots to drill. 1 or 2 will land goofy in the machined surface the diff sits on so the drill bit tends to want to walk if you don't have a good center mark.

Kit for all parts needed if you modify your current housing or a later IFS (86-95) housing to accept a e-locker diff:

Genuine Toyota® E-Locker Retrofit Kits & Parts

Retrofitting a Factory Toyota 8" Elocker diff into a non elocker 8" axle housing? Here are the Genuine Toyota parts you will need! We also offer a universal Elocker wiring harness here. Full Retro Kit: M8x1.25 Drill & Tap kit 1 Genuine Toyota Elocker Gasket 2 Genuine Toyota Long studs w/ nuts...

www.yotamasters.com

 

[pappy]

E-locker diff will fit in your front and/or rear current housings. Going with a taco rear axle will make it ~2" wider in the rear than the front with IFS hubs.

... it's very straight forward if you have a grinder, drill and tap. You can use the gasket as a template for the cut. Prior to drilling, I would then install the diff, and use the correct size center punch to mark your spots to drill. 1 or 2 will land goofy in the machined surface the diff sits on so the drill bit tends to want to walk if you don't have a good center mark.

Kit for all parts needed if you modify your current housing or a later IFS (86-95) housing to accept a e-locker diff:

Genuine Toyota® E-Locker Retrofit Kits & Parts

Retrofitting a Factory Toyota 8" Elocker diff into a non elocker 8" axle housing? Here are the Genuine Toyota parts you will need! We also offer a universal Elocker wiring harness here. Full Retro Kit: M8x1.25 Drill & Tap kit 1 Genuine Toyota Elocker Gasket 2 Genuine Toyota Long studs w/ nuts...

www.yotamasters.com

My thoughts. I'm in the process of modifying a front solid axle for an electric locker. It's not as simple as suggested. There is one good video on the subject on Youtube. The rest are garbage. The u-bolts will not clear the diff and the housing needs to be ground down. In addition there is one cap bolt that needs to be modified. I didn't like what others had done so I countersunk the hole. I only needed to countersink one bolt, but I decided to do both. Just make sure the countersink bit you use matches the angle of the bolt. I found the Home Depot/Lowes countersinks were the wrong angle. I sourced the correct countersink from McMaster-Carr.

I used a different method for drilling for the new studs. I picked a drill bit that just barely fit the diff housing hole. I ran that down into the axle housing just enough to make a crater. That gave me a better center. I then used the correct drill bit for the tap and ran it down the diff housing. That centered my bit, and kept it vertical.

Also, technically, you need to weld up a surface for the gasket. You could probably get away without doing this step, but I didn't want to take a chance. A buddy with mad skills did it for me.

This picture shows the countersunk bolts on that cap. It also shows where I needed to grind to clear the u-bolts.

Picture of before I had the surface welded and ground flat. You can see the new stud hole is right on the edge. Could this work? I don't know, and didn't want to find out.

After welding and grinding.

 

[bkg]

Unless you have plans to buy an aftermarket front housing in the future, skip the Tacoma rear axle. Too much work for no gain.

Ifs rear axle modified for elocker is popular and has been done for over 20 years.

I personally thing the IFA hubs up front is the right mod, along with FRORF Tacoma brake mods… but only if updating steering as well. If staying on factory push/pull, the additional scrub radius will be annoying.

 

[Sandman434]

I think where the confusion is coming from is the thread you quoted. The IFS (2nd Gen pickups) rear axle from 86- 94 or 95 is 3" wider than the original rear axle housing in your 82 which is a 1st gen pickup.

The 8" E-locker will still fit any of the housings but you will have to grind a notch and change a stud or something.

Guys that do a SAS on an 86- up IFS truck had to run 1 1/2" wheel spacers on the 85 and earlier straight front axles to match the width of the IFS rear axles. There is another option that is better than wheel spacers now but my point is that the 86- up rear axles are wider than the 85 and earlier.

Tacoma rear axles are even wider than the 86- 95 mini trucks.

The hubs being mentioned are not the"locking" hubs. @gnob is referring to the wheel hubs. They push the wheel mounting surface out and you don't need to run spacers to match the rear axle width. You can also upgrade to larger brakes with a slip on type rotor.

Locking hubs ARE different between the straight axle and IFS. If you're running the 85 straight axle, run the 85 locking hubs. There is a conversion kit to run IFS locking hubs on a straight axle but no need to if you have the correct ones.

I am aware of the difference in overall axle widths - the thread seemed to indicate that the 1979 rear (matching mine) and Tacoma rear had the spring perches in the same location. Was hoping that would be a more direct option than the axle modification and installing a locker, particularly due to my lack of comfort with messing with gears and not having a good setup to do so.

Those wheel hubs were the ones I found, too - there is a set for sale already machined down (relatively) close to me that I was looking at. Not intending to change the locking hubs.

 

[Sandman434]

i like the ifs hubs for width, plus it makes the brake maintenance way more convenient.

yes. it also helps with wheel choices.

the og problem with ifs wheels on a sa front is the steering arm/tre contacts the wheel. this problem is lessened or avoided using hysteer.

So without changing to a wider axle on the rear, I guess you just "live with" (live width lol?) a narrower track on the rear vs the front?

 

[Sandman434]

This link has a good overview of different Toyota axle widths that I've found useful as I've been playing around with what I want to do on the rear (full float conversion)

Toyota Axle Widths: 21 of 'em for Axle Swaps

The most Toyota axle widths you've ever seen: Specs and gotchas for minis, 4Runners, Tacos, T100s, and 40, 55, 60, and 80 Series Land Cruisers.

www.roundforge.com

E-locker diff will fit in your front and/or rear current housings. Going with a taco rear axle will make it ~2" wider in the rear than the front with IFS hubs.

If you modify the current housing, or a later IFS housing, it's very straight forward if you have a grinder, drill and tap. You can use the gasket as a template for the cut. Prior to drilling, I would then install the diff, and use the correct size center punch to mark your spots to drill. 1 or 2 will land goofy in the machined surface the diff sits on so the drill bit tends to want to walk if you don't have a good center mark.

Kit for all parts needed if you modify your current housing or a later IFS (86-95) housing to accept a e-locker diff:

Genuine Toyota® E-Locker Retrofit Kits & Parts

Retrofitting a Factory Toyota 8" Elocker diff into a non elocker 8" axle housing? Here are the Genuine Toyota parts you will need! We also offer a universal Elocker wiring harness here. Full Retro Kit: M8x1.25 Drill & Tap kit 1 Genuine Toyota Elocker Gasket 2 Genuine Toyota Long studs w/ nuts...

www.yotamasters.com

My thoughts. I'm in the process of modifying a front solid axle for an electric locker. It's not as simple as suggested. There is one good video on the subject on Youtube. The rest are garbage. The u-bolts will not clear the diff and the housing needs to be ground down. In addition there is one cap bolt that needs to be modified. I didn't like what others had done so I countersunk the hole. I only needed to countersink one bolt, but I decided to do both. Just make sure the countersink bit you use matches the angle of the bolt. I found the Home Depot/Lowes countersinks were the wrong angle. I sourced the correct countersink from McMaster-Carr.

I used a different method for drilling for the new studs. I picked a drill bit that just barely fit the diff housing hole. I ran that down into the axle housing just enough to make a crater. That gave me a better center. I then used the correct drill bit for the tap and ran it down the diff housing. That centered my bit, and kept it vertical.

Also, technically, you need to weld up a surface for the gasket. You could probably get away without doing this step, but I didn't want to take a chance. A buddy with mad skills did it for me.

This picture shows the countersunk bolts on that cap. It also shows where I needed to grind to clear the u-bolts.

View attachment 3924632

Picture of before I had the surface welded and ground flat. You can see the new stud hole is right on the edge. Could this work? I don't know, and didn't want to find out.

View attachment 3924633

After welding and grinding.

View attachment 3924634

Replying to both of these since they are related to modifying the existing housing. I've seen several write ups and videos about doing that: honestly, that's something I'm hesitant about venturing to do myself, due to not having a good work space setup, messing with gears myself, and the potential time sink. Not expecting that any option is just a quick 3-4 hour job, but the hope of finding a complete axle for $700-800 and swapping it in (if it were that "easy") seemed better than what feels like the other current option of having a shop do the modification and installation for me.

@pappy, do you have the link to the YouTube video you mentioned as the good one?

 

[Sandman434]

IDK what boosters and master cylinders fit the 1st gen trucks like yours. Since you're changing basically the entire braking system, you're most likely going to need to run an adjustable proportioning valve. Unless you find some kind of complete kit somewhere.

IDK how the rear drum parking brake is actuated in a 1st gen truck other than it is a cable. If your new rear axle has disc brakes ??? There are electric actuators out there to adapt.

As far as ABS, None of it will be operable so remove or don't use anything ABS. You'll have a pieced together system that you'll need to match components well enough that it will work properly and you can dial in.

You have a lot of choices in parts to sort through so confirm your choices before you start buying anything.

Tacoma rear axle (and the other pickups) still have the drum brakes, I've seen discussion about different solutions for the parking brake when doing a rear disc brake conversion, so I assumed that wouldn't be necessary with drums staying on the rear....but you know what they say about that

 

[gnob]

So without changing to a wider axle on the rear, I guess you just "live with" (live width lol?) a narrower track on the rear vs the front?

i don't really see doing one without the other.

 

[Sandman434]

i don't really see doing one without the other.

Makes sense. So that could just be the rear axle from an IFS truck. My idea of the Tacoma rear would actually make it sit a bit wider in the rear, so that at least would be avoided.