Adding F/R lockers to 2003 Land Cruiser (1 Viewer)

[sdnative]

I am about to embark on a journey to add front and rear lockers to my 2003 Land Cruiser. I will try to document my efforts for posterity and I am sure I will have questions along the way. Advice, tips/tricks or lessons learned are always welcome. Let me know if there is something specific you want to know/see as well.

Back story. I purchased a factory locked axle from a 98 or 99 which has been sitting in the garage for about a year now waiting to be installed. Based on my research I could either swap in the entire axle, but would have to deal with brake lines, ATRAC stuff, possibly additional sensors and wiring -or- I could swap in just the third member, the passenger axle shaft and grind some amount of material from the housing to clear the locked third member. I was leaning towards the latter. Since the ratio of the donor axle (4.30) was different than what was in there (4.10), I needed to re-gear one or the other. I was leaning towards re-gearing the rear as I didn't want to mess with the factory setup front. Well, after breaking my front diff recently I had the opportunity to reconsider.

I think I broke my front diff what are my options?

Before deciding what to do with the front, I wanted to get the rear sorted out. The outcome of that would drive at a minimum what ratio the front needed to be.

Start with the rear.

Donor axle, ECU, partial harness and switch

Third member.

Housing.

How does this look? Gears look OK?

 

[sdnative]

These are the threads I have been referencing

Elocker in a 2003+

https://forum.ih8mud.com/threads/99-locker-in-a-2000-axle-compatibility.734996/

Using 1999 diffs in a 2000+ LC/LX?

'99 LC Locked Axle into '01 LX Swap

https://forum.ih8mud.com/threads/rear-axle-swap-questions.930795/

Axle Swap (1998-1999 e-locker) into a 2000

https://forum.ih8mud.com/threads/100-lc-rear-end-question.333253/

With or without Rear Diff Lock

To swap in my factory locked axles into my 1992 or not?

Melted Diff Lock Harness 1999 LC

98-99 Rear Diff lock in High Range

https://www.toyota-tech.eu/wire_harness_rm/RM06H0E.pdf

In search of the elusive rear diff lock ecu

Short side axleshaft mod?
Twisted Splines

Spare connector under left rear?

 

[sdnative]

Couple of questions. Does anyone know where and how much needs to be removed from the housing to fit the locked third? Also, how is the harness routed (i.e. path from axle to undercarriage, how/where it enters the body, etc)? Pictures would be great.

What is the best way to store the third member, housing and axle shafts short term? Are they ok sitting in the garage uncovered/unprotected?

 

[abuck99]

Couple of questions. Does anyone know where and how much needs to be removed from the housing to fit the locked third? Also, how is the harness routed (i.e. path from axle to undercarriage, how/where it enters the body, etc)? Pictures would be great.

What is the best way to store the third member, housing and axle shafts short term? Are they ok sitting in the garage uncovered/unprotected?

Trying to follow your thought process- are you using the 99 locked axle or locking your 03 with a Harrop or some other product ?

Regear if your going to taller rubber, or your armored-and you drive in mountain areas. There are some regear discussions on optimal ratios, not sure 4:30 is a worthwhile change from the 4:10 in the 5sp.

Either way the ring gear has to come off for a locker install so now is the time to make your “informed” decision since your doing front and rear. Just Differentials might be a good sounding board for choosing ratios since they have a lot of Toyota experience- 100 & 200 series recently.

Whats removed from the housing to fit a locker? I think you have your answer from the images above? Routing wiring, lines etc: if its Harrop or ARB you’ll drill a hole the housing and install a bulk head fitting for the line or wire to pass through. The rear brake line fittings/junction is just above the thrid so you can zip tie your wires there and follow up from there.

I really like the simplicity/reliability of the Harrop E-locker. Are you doing the swaps your self? If you go that route send the thirds over to gearinstalls.com (Zuk) (I think in AZ) for set up, unless you have a local installer you trust is competent in setting up Toyota 3rds.

 

[Kofoed]

If there is a 4.3 for the front, I would go with that. The first gear of the 5sp with 4.1 is lower overall than 1st gear with the 4sp and 4.3. If there is no 4.3 for the front, what is the next common ratio, 4.88? Do you pull enough hills to warrant 4.88? I have a 1999 e locker with 4sp ,295/75 tires, and loaded down I keep up with the speed limit (except for top of Conway Summit).

I'll look at the wiring later today

 

[sdnative]

To clarify, originally I was going to re-gear the 99 locked axle to 4.10 and swap it into my 03 while leaving the front alone (this would give me rear locker only). At that time there was no need to touch the front and I didn't want to mess with the factory setup and proven front. Now that the front diff broke, I am able to rethink my strategy and decided that swapping in the rear with the factory setup 4.30 ratio while re-gearing the front to 4.30 makes more sense given the 33" tires. While I have the front apart, I am planning to add a locker, most likely Harrop. I am planning to have Zuk do the front third. I am going to do everything else myself.

4.30 diff ratio with 285/75R16 tires is about the same as the factory 4.10 diff ratio with 275/60R18 tires. So the shift points and speedo should be about the same.

Can someone confirm the axle shafts are supposed to be offset like that?

Nevermind. The axles ends weren't tightened. Once I tightened the 4 nuts they lined right up

Whats removed from the housing to fit a locker? I think you have your answer from the images above? Routing wiring, lines etc: if its Harrop or ARB you’ll drill a hole the housing and install a bulk head fitting for the line or wire to pass through. The rear brake line fittings/junction is just above the thrid so you can zip tie your wires there and follow up from there.

I was actually referring to what clearances need to be made inside the housing to fit the locked third. I know it isn't much compared the the 80 series, but some metal still needs to removed. Anyone have before and after pictures? I know I'm not the first person doing this...

 

[abuck99]

No metal needs to be removed to my knowledge- the aftermarket lockers are direct fit. If you have an air locker you just need to route the copper air delivey tube away from the ring gear.

 

[wildsmith]

afaik the semi-circular cut out on the left of your housing pictured above is what you'll need to replicate on the 2003 housing to fit the e-locker 3rd and I believe you'll need some of the longer studs from the 99 housing in some places as well.

 

[Kofoed]

I would get the Slee stone guard. IDK if it will fit on the 2003 housing, but maybe the stud patterns are the same. It took a bit of finagling, and I still haven't got the loom secured properly. The loom goes from the actuator up to the front of the upper suspension link, on top of the frame, rearward to the x-member that the leading edge of the spare rides against.

Then it crosses the top of the x-mem to the drivers side, where I lose it.....due to shoulder surgery preventing me from getting into postion....

 

[Kabanstva]

Maybe I missed it, but what brand locker are you installing in the front?

 

[sdnative]

Maybe I missed it, but what brand locker are you installing in the front?

Most likely Harrop

 

[sdnative]

I would get the Slee stone guard. IDK if it will fit on the 2003 housing, but maybe the stud patterns are the same. It took a bit of finagling, and I still haven't got the loom secured properly. The loom goes from the actuator up to the front of the upper suspension link, on top of the frame, rearward to the x-member that the leading edge of the spare rides against.

Then it crosses the top of the x-mem to the drivers side, where I lose it.....due to shoulder surgery preventing me from getting into postion....

Thanks! That helps. Sorry to make you crawl around under your truck with a sore shoulder

I would like to find out where the harness enters the body and also where the ECU is mounted. If anyone else has that info I would appreciate it. No need for pictures, just a good description like above.

 

[Kofoed]

FSM Page SA-160 etc. Best I can do right now.

BTW get the stone guard and loom mounted while pumpkin it out, if posiible

 

[Skidoo]

Please read the o.p. the question on grinding is for installing a '99 factory elocker 3rd member in a 2003 rear differential housing. Has nothing to do with aftermarket lockers.

 

[Kofoed]

afaik the semi-circular cut out on the left of your housing pictured above is what you'll need to replicate on the 2003 housing to fit the e-locker 3rd and I believe you'll need some of the longer studs from the 99 housing in some places as well.

Buy the gasket for the e locker and youll have an idea of what to cut

 

[wardharris]

Cannot add any tech, but this is the combination my partner Georg from Valley Hybrids @orangefj45 has in his '99 Hundy - OEM rear and Harrop front. He is a very happy boy.

Good luck with the swap/install - here's some motivation

G working both elockers at Pismo a few years ago.....

 

[sdnative]

Is it necessary to replace the rear axle seals, bearings, retainers, etc? I was planning to do all of that "while I was in there", but it looks like a bit of work requiring a press, SST, etc. Not trying to be cheap, just trying to understand if it is necessary at this time. Looks like the axle can be pulled at a later date without touching the diff if it starts leaking. No leaks now.

Truck has 133k miles.

 

[orangefj45]

As @wardharris mentioned, I have the factory rear locker and the Harrop front locker in my 100 and they've performed flawless for the last couple of years since I installed the front. The rear has never had any issues and is origibal to the vehicles.

If you're removing the axles from the rear, then it's a good idea to replace the o-ring on the back side.
Part number 90301-85004

Georg @ Valley Hybrids & Cruiser Brothers

 

[sdnative]

Spent the last few days cleaning out the garage so I'll have plenty of space and not be tripping over things. Ordered parts and this weekend I'll drain the diff and pull the axles/third from the truck. At that point I can assess what grinding needs to be done.

 

[sdnative]

Removed the spare tire and swaybar to make room to work. Removed rear driveshaft, calipers, e-brake cable, etc.

Disconnected the brake line and reattached on the outside of the bracket. Removed the ABS sensor.

ABS sensor had some fluid on it. I take it that's not normal? Same on both sides. The ABS tone rings looked dry though.

Removed the 4 nuts holding the axles in and pulled them out enough to clear the diff.

Supported the axles so they weren't resting on the seals.