Build 1998 HDJ80 with 1HDT - Refresh

[logicbyondreaso]

Before I fully broke down the diff, I did a pattern check on the gears which supposedly have more than a half a million miles on them.
In order to hold the pinion flange I modified my @OTRAMM crank pulley tool for use with both front and rear diffs. This will come into play during final assembly.
Finally I cleaned all the hardware and organized them for easy assembly in case this project takes longer to do than expected.
New bearings and seals on the way from Toyota.

 

[logicbyondreaso]

A few updates to the axles.
I stripped both front and rear axles and then did a deep degreasing session in prep for paint.
The internals of each axles were cleaned and inspected.
Using a combination of wire wheels, I removed any loose paint and cleaned out surface rust spots.
The pumpkin hole and axle ends were bagged and taped off.
I applied 2 coasts of primer and then 3 top coats. I used Rust-Oleum Farm Implement low gloss black paint.
You can see all the factory weld splatter in the last photo.

 

[logicbyondreaso]

All 4 hubs were cleaned and bearing races removed and new oem installed.
I cleaned up the rear dust shields and painted them with the same paint as above. They were in very good shape. I will be overhauling the parking brake system later on.

I then switched my attention over to replacing the carrier bearings. For the rear e-locker the cover plate needs to be removed to press out the bearing from the back end. Well, most of the 6-point bolts sheared. They are held in with blue loctite and even after some heat they did not budge. I ended up welding on nuts to back them out. I prefer this method as the welding adds enough heat to break the bond and give you a new bolt head to turn by. No damage is done to the parts.

 

[logicbyondreaso]

Both the differentials were stripped of the carrier, pinion, bearings, and seals. Then I degreased and removed any flaky paint.
Unpainted areas were masked off.
Using the same paint as before, Rust-Oleum Farm Implement, I sprayed them with 3 coats.
New bearing races were pressed in. Old bearings and races were in great shape. I am going to keep them as spares. I was not expecting the condition to be this good with the mileage they have.

I am using an inspection mirror to verify the bearing race is seated all the way.

I use bearing driver pucks to get the right size and spacing for the 20-ton press.

 

[logicbyondreaso]

I pressed on new carrier bearings and started with an initial shim for the pinion. Once I get a pattern I will know what adjustments to the shim are needed.
Both front and rear inner seals were installed using the seal driver tool.
During inspection of the birfs, I noticed wear from the balls. This will happen over time and eventually will cause clicking. I don't know if they clicked or not before I got them so I decided to replace with new. Cruiser Outfitters were out of stock of their Japan made alternatives so I ended up purchasing new oem elsewhere. The shafts had seal wear so I decided to replace them now too and keep the old as spares.

Does anyone have long-term review of the Terrain Tamer Heavy Duty Inner Hub Seal? I am considering using them for the rears since there is some wear and in theory the TT seals should prevent further damage. This type of seal is very common in tractors and heavy duty machinery so just curious how they hold up for the 80 series application.

 

[logicbyondreaso]

I had someone drop off their JDM HDJ81 for maintenance that turned into a lot of work and baselining. That is now complete and I returned my focus to completing the locked axles rebuild.
New birfs and miscellaneous hardware for the axles arrived from Japan after 6 weeks from ordering.

I finished rebuilding the front and rear e-locker differentials using all new oem bearings, shims, and seals where applicable. Final results in the table below.

	Front	Rear
Pinion Shim	2.03 mm	1.225 mm
Pinion Preload	12 in-lb	13 in-lb
Carrier Bearing Preload	5 in-lb	6 in-lb
Backlash	0.18 mm	0.17 mm

 

[glinskonian]

I have made an effort to source the right tachometer for a manual 1HDT but have come up empty. A couple sources potentially had it but there were defects and the sellers were asking more than I wanted. My solution is to keep the A/T ECU but since the clutch pedal took its spot it would need to be moved. I picked up matching connectors and extended the harness by 3' so I can mount the ECU under the driver seat. Same place as the factory alarm box. All the wires were soldered, heat shrunk, and then wrapped in a wire loom. Works just as expected.

During this work I replaced the gear position indicator with a blank to finish off the manual conversion. I did enjoy having the reverse light come on when reversing.

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Loving this thread, excellent work!
I am in the process of swapping a H152 into my 80 (1FZ) and wanted to share my solution for mounting the A/T ECU.
I 3D printed this bracket that relocates the ECU onto the clutch pedal itself.
It required some cutting of the bracket arms like you did but nothing crazy.

One of the arms connects to my 3D printed mount, and the other arm leverages the bolt that secures the upper part of the clutch bracket to the upper(?) firewall.

I still had enough length in the connector, and there's no interference with the clutch or anything else.

 

[glinskonian]

Loving this thread, excellent work!
I am in the process of swapping a H152 into my 80 (1FZ) and wanted to share my solution for mounting the A/T ECU.
I 3D printed this bracket that relocates the ECU onto the clutch pedal itself.
It required some cutting of the bracket arms like you did but nothing crazy.

One of the arms connects to my 3D printed mount, and the other arm leverages the bolt that secures the upper part of the clutch bracket to the upper(?) firewall.

I still had enough length in the connector, and there's no interference with the clutch or anything else.

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And yes I cut off some of the flange for one of the bolts that goes through the firewall, it's a long story lol

 

[logicbyondreaso]

@glinskonian - nice work! What does the printed part look like? Are you going to share/sell it for others to try?

 

[Dilspec]

Incredible work, thanks for sharing.

 

[glinskonian]

@glinskonian - nice work! What does the printed part look like? Are you going to share/sell it for others to try?

Here it is in CAD. It's fairly simple really, but I think it's a nice way solve the problem and take advantage of the clutch pedal that's right there.
I do plan to sell these along with some other stuff I've printed soon.

 

[logicbyondreaso]

Got both axles completed and ready to be installed. I am going to look at the HF2AV gearbox to see if it requires any service before swapping it in.
Once the axles are installed, I will get the wiring installed to get the lockers functional.