80 series rear axle with front axle Tundra brake mod (6 Viewers)

[Godwin]

It's a tight fit between the e-locker actuator guard and the shock. The shock rubs a little on the edge of the guard. It's also been an annoyance for pulling the guard because I'd have to loosen the lower shock mount and pull the shock forward some to be able to free the guard.

From photos of the Slee guard, which is substantially stouter than the stock, I thought that it would bolt up without interference, and it almost does. The Slee guard is designed for the 80 series and not a modified 80 series axle under a 60 and I found that there was interference with shock but that was easily corrected by trimming a corner of the guard.

Mounting was a little tricky because it's done by feel.

 

[4runner2FJ60]

@Godwin EXCELLENT write up and thank you! The gearing stuff is fairly new to me, but can the 3.7 OE diffs go into the 80 housing in the rear? I would like to keep the front that way if possible. Running the OE 4 speed and like how it works with 33s. Maybe since I have not driven anything with the 4.11 I wouldn't notice any difference, but I do know they have to match if I want to use 4x4. I also have an 84, so maybe someone can chime in on compatibility issues if any? Thanks again!

 

[cruisermatt]

@Godwin EXCELLENT write up and thank you! The gearing stuff is fairly new to me, but can the 3.7 OE diffs go into the 80 housing in the rear? I would like to keep the front that way if possible. Running the OE 4 speed and like how it works with 33s. Maybe since I have not driven anything with the 4.11 I wouldn't notice any difference, but I do know they have to match if I want to use 4x4. I also have an 84, so maybe someone can chime in on compatibility issues if any? Thanks again!

yes just move your third member over to the new housing.

 

[Godwin]

@Godwin EXCELLENT write up and thank you! The gearing stuff is fairly new to me, but can the 3.7 OE diffs go into the 80 housing in the rear? I would like to keep the front that way if possible. Running the OE 4 speed and like how it works with 33s. Maybe since I have not driven anything with the 4.11 I wouldn't notice any difference, but I do know they have to match if I want to use 4x4. I also have an 84, so maybe someone can chime in on compatibility issues if any? Thanks again!

If you use a non-locking 80 series rear housing your 3.7 diff will drop right in. Non-locking rear axles are more common and cheaper so that's a good thing. Check with @slow95z on axle availability.

If you're going to stay with the H42 then running 3.7s will be better, especially for highway speeds.

 

[Godwin]

I'm almost three years into having done these mods and recently had two brake issue crop up. The most recent was this week when I lost an upper caliper bolt for the right front caliper. When I did the Tundra brake mod I swapped calipers right to left and that places the square fill plug on the backside of the knuckle. This also introduces an interference with using a socket on the upper caliper bolt so you can tighten it tight but cannot use a torque wrench to know that you've hit that 90 ft-lbs of torque. While on trip this week I lost the upper bolt on the interstate, actually heard it hit the underside of the 60 but simply thought I'd run over something. At the next gas stop the loose caliper was evident. I checked it and noticed the lost bolt. I rolled on down the interstate a few miles to the next exit and found an Ace Hardware that had a 12 X 1.25 bolt that would work, but only in the bottom. The bolt was too long to fit in past the fill plug.

Sometime later this year I am planning on rebuilding these knuckles and will swap the knuckles back to the original sides and that will necessitate grinding off the caliper mounts.

About 3 months ago I had an issue develop one of the rear calipers where a brake pad was ground away and the piston was in contact with the rotor. I replaced the pads and bought a new piston and seals. Today I pulled the caliper apart to discover why the pad and piston had been ground down, one fo the sliders was rusted and the caliper could not slide properly. Lesson learned is to grease the sliding pins on these calipers. Left rear was ok and has now been greased. I have new caliper on order and those pins will be greased as well.

 

[cruisermatt]

You could also just replace the knuckle fill plug with a allen/hex key type.

Weird I have never had a issue getting a socket on my caliper bolts.

 

[4runner2FJ60]

And here I was thinking I might get out of swapping knuckles side to side! All good info, and in preservation of the knuckle caliper mounting ears, its probably worth swapping. Not trying to start another debate here......

 

[4runner2FJ60]

Still working on these mods. I finally split the diff from axle to inspect the insides. The gears all visibly look great. Tested backlash in 5 different places on ring, all coming back at .007" Considering running a contact patch test. Noticed a ringing noise coming from the pinion seal dust cover. I think it might just be bent a small amount or is hitting a little rust spot? Anyone want to chime in on this? Also since I have gone this far, should I leave it alone, paint and install, OR bite the bullet, disassemble and installed new bearings, pinion seal....etc??? Thanks for your suggestions and advice.

 

[cruisermatt]

Pry the dust cover a little with a flat screwdriver to fix the rub. .007 is loose but OK. How many miles? Unfortunately the E-locker rear isn’t quick adjustment like the normal carriers.

 

[4runner2FJ60]

Thanks, I'll contact the PO to see if he knows the mileage on it as I do not. It falls in that 94-97 range with abs. I noticed the lack of side adjusters, I was not expecting this. Looks like a pain to make adjustments to.

 

[4runner2FJ60]

No idea the mileage? I read on a thread that the pinion bearings on the 80 diff have a tenancy to go bad, But I don't know that for a fact? So are the adjustments on the carrier bearings done with shims only? I can't find any info or pictures where someone rebuilt one of these. Still searching thru ZUK's website and builds.....
Another post said the carrier bearings are so large they last a long time, basically saying to change the pinion and reseal on these factory locked ones?

 

[cruisermatt]

No idea the mileage? I read on a thread that the pinion bearings on the 80 diff have a tenancy to go bad, But I don't know that for a fact? So are the adjustments on the carrier bearings done with shims only? I can't find any info or pictures where someone rebuilt one of these. Still searching thru ZUK's website and builds.....
Another post said the carrier bearings are so large they last a long time, basically saying to change the pinion and reseal on these factory locked ones?

Correct, shims only, and yes usually outer pinion bearing is due for replacement at +250k miles from my experience. Install a solid pinion spacer at the same time.

 

[4runner2FJ60]

I'm on and off the fence with this one. Found lots of great info on Zuk's site which gave me confidence to do this, But I know he is like a Jedi Differential guy and makes it look easy. Wonder if i should just run it and see to save myself alot of possible frustration. Thanks again!

 

[Godwin]

Replaced the rear Bilstein shocks which have been on for 3 1/2 to 4 years. Shocks are still good and will be going onto this 1985 3FE Swapped FJ60, a Refresh - https://forum.ih8mud.com/threads/1985-3fe-swapped-fj60-a-refresh.1309046/. The refreshed 60 received low mileage OME suspension from my 60 and swapping over the old, but good, Bilsteins is continuing this trend. It now also has the old H55F out of my 60.

The passenger side shock body has rubbed on the edge of the Slee acuator guard, not bad but it's something I need to watch. This has only happened when we've driven the 60 in the rocks which has given the suspension a good workout. I also replaced the lower shock mount bolts with new since the old ones were hammered. The large shock washers had been smushed over onto the shock mounts. New front shocks will be installed in the next couple of weeks once I have them.

These shocks are pressurized and mounting them is a fight.

 

[Godwin]

4 years and at least 80k and maybe closer to 100k miles on the 80 series FF axle and Tundra brake mod.

This entire time I've run only gear oil in the rear axle, the inner axle seals were never installed. I'm still on the bearings that I initially installed in the FF axle. The diff had been rebuilt by Zuk and he recommended synthetic Mobil 1 for the gear oil and that's what I've been using.

Last week I tore down the front knuckles for a rebuild.

 

[Godwin]

I'm replacing all the fasteners with new OEM, removing the caliper ears from the knuckles, and swapping the knuckles back to the original side. Everything is apart, cleaned and painted and I expect to have the job completed this weekend. Knuckle centering tool will be used to properly set the orientation and preload of the knuckles.

 

[Godwin]

In another thread on the Tundra brake mod the dust shield was flipped which required trimming the edges. I installed the dust shield as normal and found no issues when I disassembled.

 

[4runner2FJ60]

@Godwin Did you cut off the ears because you never imagine going back to factory brakes? Or was there another reason? I swapped sides with mine as well and re-checked centering at the same time. I bought brass allen head plugs for the grease port. Also running the dust shield the factory way without issues.

 

[Godwin]

@Godwin Did you cut off the ears because you never imagine going back to factory brakes? Or was there another reason? I swapped sides with mine as well and re-checked centering at the same time. I bought brass allen head plugs for the grease port. Also running the dust shield the factory way without issues.

I cut off the ears because I decided these knuckles will never go back into a stock configuration. I also wanted the fill plug back in the anterior orientation.

 

[Godwin]

@Godwin Did you cut off the ears because you never imagine going back to factory brakes? Or was there another reason? I swapped sides with mine as well and re-checked centering at the same time. I bought brass allen head plugs for the grease port. Also running the dust shield the factory way without issues.

Where did you find a brass allen head plug for the fill port?