Rolling in Park? (1 Viewer)

[Jedijunk]

Well, following the advice of @flintknapper , I tested and confirmed that the car rolls in park in High range, but not when the center diff is locked in low range. So I had high hopes it was just a stripped drive flange.

So we put the beast on a lift at the mechanic's shop today. But when I pulled the front wheels, the drive splines look healthy to me (pics of the right side splines attached). So then I tried some of the other tests you guys described.

With all 4 wheels off the ground, shifter in Park, and center diff selector in High, I can spin either front wheel easily. When I turn either front wheel, the other front wheel doesn't turn at all but the front driveshaft does turn freely (the rear drive shaft stays still). Neither rear wheel can be turned at all (the parking brake is off). The rear driveshaft didn't move at any point during my testing of the 4 wheels.

Does all of that sound normal, or indicate a problem?

Tomorrow I'll have the mechanic open up the front diff to inspect the gears. If those are OK too, what do I check after that? The garage here would obviously like the root issue of all of this to have been the transmission problem they said it was from the beginning. So they are saying they want to adjust the shifter cable again. I basically have to lead them to the real problem here or they won't admit fault in an unnecessary tranny swap. Please share any additional knowledge you have with me!

 

[Jedijunk]

Unrelated aside, but I had them pull the AC evaporator to check it for leaks and clean it today. I've never seen one so dirty - there was a quarter inch of mud-dust built up on the dirty/intake side! Obviously the previous owner never had it cleaned - it was DISGUSTING (pic attached). After spraying it down we leak tested it and it was leaking too. So now I get to drop $200 on a used replacement. Parts are hard to come by here in Cambodia!

 

[Jedijunk]

Then why does the truck move under power but park can't hold it on a slight hill? You can have one or the other, not both.



VC's don't work like this. When they work, they barely transfer enough power to move the truck if one wheel has no traction, for whatever reason. The overrevving and complete lack of power is very obvious.



A normally functioning VC won't 'lock', it transfers a (small) percentage of power.

All I'm saying is that there may be an issue with the flange, or not, or several issues. Or it could be a stripped flange and the system is doing something it shouldn't be able to- slip in Park but apply power from the engine. Or the OP isn't explaining what is happening accurately.

I'd like to understand this possibility of a cooked/locked VC better. If mine isn't cooked/locked, it probably SHOULD be after what I did to it. My first off-road outing with my new LX450 (after having the drivetrain inspected and doing a few minor repairs like having the front hyme joints replaced) was camping all alone with my young kids down at a stream out in the Cambodian jungle. It handled a long uphill crawl just fine so I figured things were all good with the drivetrain, and I headed down a steep/sandy (but doable) bank to a campsite on a stream. I discovered that it felt like something was slipping when I was ready to pull out of there, with no way to go but up. So I thought "the clutch plates are toast - I've got to grind out of here and fix it later, or let it die trying!". I hammered the throttle, made it up that steep bank (on the third run at it) to a gravel road, used good momentum management to baby it up several more long grades on the gravel road, and then made it back to town on 80 miles of fairly flat paved road. So if the tranny was actually fine and the VC was slipping through all of that, it REALLY deserves to be cooked.

How would I test the VC/center diff? When it was up on the lift today, in Park with the transfer case in High, I spun a front wheel and the front drive shaft turned at the same time, but the rear drive shaft did NOT turn. Does that mean that the VC is working and isn't cooked/locked?

 

[BILT4ME]

Well, following the advice of @flintknapper , I tested and confirmed that the car rolls in park in High range, but not when the center diff is locked in low range. So I had high hopes it was just a stripped drive flange.

So we put the beast on a lift at the mechanic's shop today. But when I pulled the front wheels, the drive splines look healthy to me (pics of the right side splines attached). So then I tried some of the other tests you guys described.

With all 4 wheels off the ground, shifter in Park, and center diff selector in High, I can spin either front wheel easily. When I turn either front wheel, the other front wheel doesn't turn at all but the driveshaft between the front diff and center diff does turn freely. Neither rear wheel can be turned at all (the parking brake is off) and the rear driveshaft doesn't move when any of the wheels are turned.

Does all of that sound normal, or indicate a problem?

Tomorrow I'll have the mechanic open up the front diff to inspect the gears. If those are OK too, what do I check after that? The garage here would obviously like the root issue of all of this to have been the transmission problem they said it was from the beginning. So they are saying they want to adjust the shifter cable again. I basically have to lead them to the real problem here or they won't admit fault in an unnecessary tranny swap. Please share any additional knowledge you have with me!

View attachment 2731795

View attachment 2731796

That drive flange is worn, but not ground out. What's the other one look like? It only takes one to make this problem.

Does this truck have locking differentials?
Does this truck have a separate CDL switch?
Has the Pin 7 Mod been done to this truck if it has had a CDL switch installed?

Talking about the wheels spinning by hand:
"Neither rear wheel can be turned at all (the parking brake is off) and the rear driveshaft doesn't move when any of the wheels are turned."
Your description here is odd.
If you spin one wheel EITHER the opposite wheel will rotate the opposite direction OR the driveshaft will turn, or some of both. Since the truck is in park, the DS should NOT turn.
If you cannot turn either wheel, yet the DS doesn't turn when wither wheel is turned? You're telling me nothing is turning, yet it's turning? Very confusing statement.

With the truck in the air, there are a few scenarios that will take place:
SCENARIO 1:
Transmission in PARK.
Transfer case in HIGH.
CDL switch UNLOCKED.
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction OR the DS should turn.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction. DS cannot turn due to being in park.

SCENARIO 2:
Transmission in PARK.
Transfer case in HIGH.
CDL switch LOCKED.
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction. DS cannot turn due to being locked to rear DS and transmission in park.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction. DS cannot turn due to being in park.

SCENARIO 3:
Transmission in PARK.
Transfer case in LOW. (After key on to allow CDL to lock)
CDL switch LOCKED (Due to Low Range)
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction. DS cannot turn due to being locked to rear DS and transmission in park.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction. DS cannot turn due to being in park.

SCENARIO 4: (I need some back-up here. I am not 100% positive this transfer case behave this way)
Transmission in PARK.
Transfer case in NEUTRAL.
CDL switch LOCKED.
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction OR DS will turn, also turning the REAR DS and will turn at least one rear tire or BOTH tires in the SAME direction.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction OR DS will turn, also turning the FRONT DS and will turn at least one front tire or BOTH tires in the SAME direction.

These trucks are known for blowing out a front ring and pinion when doing things hard in reverse. If you were stuck bad and gouging on it in reverse, you may have destroyed your front R&P. If so, some of your scenario would show true. Drain the front differential and look for lots of shiny pieces

If your front DS will rotate by hand separately from the rear DS, your VC is not burned out, or it's missing.

 

[Jedijunk]

That drive flange is worn, but not ground out. What's the other one look like? It only takes one to make this problem.

Does this truck have locking differentials?
Does this truck have a separate CDL switch?
Has the Pin 7 Mod been done to this truck if it has had a CDL switch installed?

Talking about the wheels spinning by hand:
"Neither rear wheel can be turned at all (the parking brake is off) and the rear driveshaft doesn't move when any of the wheels are turned."
Your description here is odd.
If you spin one wheel EITHER the opposite wheel will rotate the opposite direction OR the driveshaft will turn, or some of both. Since the truck is in park, the DS should NOT turn.
If you cannot turn either wheel, yet the DS doesn't turn when wither wheel is turned? You're telling me nothing is turning, yet it's turning? Very confusing statement.

With the truck in the air, there are a few scenarios that will take place:
SCENARIO 1:
Transmission in PARK.
Transfer case in HIGH.
CDL switch UNLOCKED.
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction OR the DS should turn.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction. DS cannot turn due to being in park.

SCENARIO 2:
Transmission in PARK.
Transfer case in HIGH.
CDL switch LOCKED.
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction. DS cannot turn due to being locked to rear DS and transmission in park.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction. DS cannot turn due to being in park.

SCENARIO 3:
Transmission in PARK.
Transfer case in LOW. (After key on to allow CDL to lock)
CDL switch LOCKED (Due to Low Range)
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction. DS cannot turn due to being locked to rear DS and transmission in park.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction. DS cannot turn due to being in park.

SCENARIO 4: (I need some back-up here. I am not 100% positive this transfer case behave this way)
Transmission in PARK.
Transfer case in NEUTRAL.
CDL switch LOCKED.
FRONT:
Rotate a front tire, the opposite tire should rotate opposite direction OR DS will turn, also turning the REAR DS and will turn at least one rear tire or BOTH tires in the SAME direction.
REAR:
Rotate a rear tire, the opposite tire should rotate opposite direction OR DS will turn, also turning the FRONT DS and will turn at least one front tire or BOTH tires in the SAME direction.

These trucks are known for blowing out a front ring and pinion when doing things hard in reverse. If you were stuck bad and gouging on it in reverse, you may have destroyed your front R&P. If so, some of your scenario would show true. Drain the front differential and look for lots of shiny pieces

If your front DS will rotate by hand separately from the rear DS, your VC is not burned out, or it's missing.

Ok this is SUPER helpful. Thank you for taking the time to explain this! My LX450 only has the center diff locker that automatically locks when Low range is selected. There is no separate switch to choose when to lock/unlock the center diff. No front or rear locker installed as far as I know. I have never heard of the "Pin 7 Mod" so I haven't done it. I would guess the P.O. didn't either. He seems to have been a "drive it for what it is until something breaks, then find someone to fix it" kind of guy. So I'm working through lots of catch-up maintenance and repairs now. Sigh.

Scenario 1 in your list is what I tested today.
Transmission in PARK. Transfer case in HIGH. CDL UNLOCKED (I assume, because the Lock indicator light isn't on and the transfer case is in High).
FRONT:
When I rotate a front tire (either one), the front DS turns and the other front tire doesn't move.
REAR:
Sorry about the confusion in my wording. I should have said "the rear DS doesn't turn when I TRY to turn the rear wheels". Bottom line, I'm unable to rotate either rear tire at all with the car in the air, in park. The parking brake was off when I put it on the lift (unless one of the mechanics assistants put it on when I wasn't looking... now I'm wondering about that and I'll confirm tomorrow). If the rear wheels won't turn and the parking brake is off for sure, would this indicate that my problem might be at the rear axle (rear diff, rear hubs, rear drive shaft)? If it doesn't have a rear locker, but the rear wheels act locked, could some hack have welded something to make it permanently locked? But if that was the case, and the center diff is not locked, wouldn't the rear drive shaft turn and both rear wheels turn?

 

[BILT4ME]

Ok this is SUPER helpful. Thank you for taking the time to explain this! My LX450 only has the center diff locker that automatically locks when Low range is selected. There is no separate switch to choose when to lock/unlock the center diff. No front or rear locker installed as far as I know. I have never heard of the "Pin 7 Mod" so I haven't done it. I would guess the P.O. didn't either. He seems to have been a "drive it for what it is until something breaks, then find someone to fix it" kind of guy. So I'm working through lots of catch-up maintenance and repairs now. Sigh.

Scenario 1 in your list is what I tested today.
Transmission in PARK. Transfer case in HIGH. CDL UNLOCKED (I assume, because the Lock indicator light isn't on and the transfer case is in High).
FRONT:
When I rotate a front tire (either one), the front DS turns and the other front tire doesn't move.
REAR:
Sorry about the confusion in my wording. I should have said "the rear DS doesn't turn when I TRY to turn the rear wheels". Bottom line, I'm unable to rotate either rear tire at all with the car in the air, in park. The parking brake was off when I put it on the lift (unless one of the mechanics assistants put it on when I wasn't looking... now I'm wondering about that and I'll confirm tomorrow). If the rear wheels won't turn and the parking brake is off for sure, would this indicate that my problem might be at the rear axle (rear diff, rear hubs, rear drive shaft)? If it doesn't have a rear locker, but the rear wheels act locked, could some hack have welded something to make it permanently locked? But if that was the case, and the center diff is not locked, wouldn't the rear drive shaft turn and both rear wheels turn?

It could mean that the brakes are just too tight (dragging calipers) and you just cannot turn them manually. You would need to remove the rear wheels and pry the pads away from the rotors to push fluid out of the calipers to allow space to let the pads release. Disc brakes do NOT have springs to "release" them. It relies on the runout and "lack of pressure" to allow the rotors to turn. Frequently this cannot be turned by hand because humans are weak.

It is also possible that you have a "lunchbox locker" in the rear that is locked (or even someone welded the spider gears) to make both rear wheels turn together 100% of the time. If you CANNOT turn one rear wheel with the truck in park and the brakes released, then there is something different in the rear, but it should NOT be causing the problem you describe about rolling in park.

Being in Cambodia (assuming that's where this truck has lived its life) there may be all kinds of shenanigans that have been done to that truck, just to make it keep going.

Now that I say that, there have even been folks on here that bought a truck, only to find out all the guts in the front differential were MISSING, yet the seller said nothing about it. I don't think that's the case here based on what you describe.

 

[Jedijunk]

It is also possible that you have a "lunchbox locker" in the rear that is locked (or even someone welded the spider gears) to make both rear wheels turn together 100% of the time. If you CANNOT turn one rear wheel with the truck in park and the brakes released, then there is something different in the rear, but it should NOT be causing the problem you describe about rolling in park.

Being in Cambodia (assuming that's where this truck has lived its life) there may be all kinds of shenanigans that have been done to that truck, just to make it keep going.

Things like this are very possible here, it's a "find a creative hack to keep it going without proper parts" kind of a place. Which I both admire and at times hate. Right now with the past work done on this truck it's more on the hate side ha ha. But eventually I expect that I'll get through to a vehicle that I can take to the jungle with reasonable confidence in that 80-series reliability.

Now that I think about it, I'm pretty sure the VC in the center diff isn't fried because I rotated a front wheel today and the front drive shaft spun but the rear drive shaft didn't move at the same time. So it sounds like tomorrow I'll be opening up the front diff to try to solve the "rolls in park" issue AND opening the rear diff to see what hack-lock wonders await (after confirming it's not a parking brake or stuck rear brakes issue). I'll also test your scenarios #3 and #4 (I don't have the switchable diff lock to test #2).

 

[leonard_nemoy]

(I don't have the switchable diff lock to test #2).

Center Differential Lock Pin 7 Mod - Slee Off Road - https://sleeoffroad.com/center-differential-lock-pin-7-mod/

 

[BILT4ME]

Things like this are very possible here, it's a "find a creative hack to keep it going without proper parts" kind of a place. Which I both admire and at times hate. Right now with the past work done on this truck it's more on the hate side ha ha. But eventually I expect that I'll get through to a vehicle that I can take to the jungle with reasonable confidence in that 80-series reliability.

Now that I think about it, I'm pretty sure the VC in the center diff isn't fried because I rotated a front wheel today and the front drive shaft spun but the rear drive shaft didn't move at the same time. So it sounds like tomorrow I'll be opening up the front diff to try to solve the "rolls in park" issue AND opening the rear diff to see what hack-lock wonders await (after confirming it's not a parking brake or stuck rear brakes issue). I'll also test your scenarios #3 and #4 (I don't have the switchable diff lock to test #2).

Yeah, just skip to #3, it will give the same results as long as you make sure the key is on or running when you shift it, confirm engagement, then shut it off for your test.

 

[Dave 2000]

Yers, they do lock. Permanently. They don't loosen up when you put the trans in Park.

Exactly!

Regards

Dave

 

[Jedijunk]

RESOLUTION UPDATE AND A FOLLOW-UP QUESTION:
Well, never underestimate the unhinged ingenuity of bush mechanics. Front diff checked out. Rear diff checked out. We opened up the transfer case, and WHAT THE?!?!? Someone either welded, or torched, or SOMETHING, the outer teeth on this gear. I don't understand exactly why - it apparently is connected to some belief here that they would get better gas mileage or make the transmission feel more "smooth"??? Does anyone have a diagram of the center transfer case for the LX450/FJ80? I don't know what this part is exactly.

What is this assembly? This is the other side of it:

At any rate, I don't know if the teeth were welded to the case and broke free when I was out in the mud, or if the teeth were torched off and I only had RWD to begin with. But this apparently set off a chain reaction that damaged front axle parts AND (according to the mechanic) the clutch plates in the auto transmission. I don't have access to a transmission shop here to verify or assess damage to the transmission, so I kept the replacement transmission in the car ($900 installed). I also swapped in another transfer case ($450 installed). Add in some front drive axles and AC work, and I'm out $2k for that little adventure.

@BILT4ME , #1 and #3 on your description check out as you described now. #2 and #4 aren't possible without a dedicated center diff lock switch (for #4 diff lock turns off when I shift the transfer case to N). And all 4 wheels drive in D, 2, and 1, with transfer case in H or L when I start the car up on the lift.

Lastly, this might be a topic for another thread, but is it worth trying to assess and rebuilld the old transmission and/or transfer case myself at home, using parts I'd have to bring over in my luggage next time I visit the USA? The transfer case seems like something I should be able to fix if I can get just that damaged part, but is overhauling an auto transmission going to take specialized tools that it isn't worth acquiring to attempt? If a rebuild is inadvisable I figure I can at least strip it for education purposes...

 

[flintknapper]

Looks like someone tried to permanently lock your Center Differential. Using the 'Lincoln Locker' method.

Rebuilding the old transfer-case should be easy enough. Transmission a bit more difficult depending on how well you are 'tooled'. A master overhaul kit should have everything you need in the way of parts. IF your transmission is the A343F then the repair manual for it is Pub. # RM998U.

 

[BILT4ME]

What you are looking at is the center differential in the transfer case. There should have been a center pin and spider gears in there as well. It looks to me like someone blew up the spiders, then welded in the sun gear to the carrier to make it move.

There is nothing about this break in the transfer case that would "set off a chain reaction" that would damage the plates in the transmission. He's trying to play on your ignorance to cover his ass.

What damage was present in your F/R differentials?

From a diagnosis standpoint, I would have gone through the front axle before replacing the transmission.

I don't think anyone here has seen a transfer case with this kind of cobble job before. They went to a LOT of work to do that.

I'll bet your old transmission is just fine.

You can engage your diff lock and have it in High range.

Key on.
Shift to low range and wait for the CDL light.
Turn key off.
Pull CDL fuse.
Pull transfer case into high range.
Run test.

You can drive it like this.

Did you replace the transfer case?
That would be the best scenario.

 

[-Spike-]

Well, that explains why it didn't look like any issue I've ever heard of. Multiple failures in multiple assemblies. Usually you look for the simplest explanation, but this one is the exception to that rule.

Thanks @Jedijunk for the follow-up.

 

[Jedijunk]

What you are looking at is the center differential in the transfer case. There should have been a center pin and spider gears in there as well. It looks to me like someone blew up the spiders, then welded in the sun gear to the carrier to make it move.

There is nothing about this break in the transfer case that would "set off a chain reaction" that would damage the plates in the transmission. He's trying to play on your ignorance to cover his ass.

What damage was present in your F/R differentials?

From a diagnosis standpoint, I would have gone through the front axle before replacing the transmission.

I don't think anyone here has seen a transfer case with this kind of cobble job before. They went to a LOT of work to do that.

I'll bet your old transmission is just fine.

You can engage your diff lock and have it in High range.

Key on.
Shift to low range and wait for the CDL light.
Turn key off.
Pull CDL fuse.
Pull transfer case into high range.
Run test.

You can drive it like this.

Did you replace the transfer case?
That would be the best scenario.

Yep, I replaced the transfer case. As far as the old transmission, now that it's been opened up by a mechanic that doesn't work on transmissions and poked around inside before he closed it back up, I'm not sure I would trust it until it had been worked over. He also pointed to damaged bolt heads inside as evidence that some other mechanic had been in there messing around. Given what they did to the center diff, who knows what they might have done in the trans!

 

[Grandlooser]

Now we would all like pics of this vehicle in case it ever comes up for sale somewhere.

 

[Njck22]

How does an LX450 get to cambodia? I was under the impression they were only ever sold in US. I have seen some russians that buy all the exteriors pieces and "convert" their landcruiser. Interesting story

 

[Jedijunk]

Now we would all like pics of this vehicle in case it ever comes up for sale somewhere.

Vehicles never make it out of Cambodia so you're safe unless you move here ha ha. When I get time I'll post a "my rig" thread. Where's the proper place for those in the forums?

 

[Jedijunk]

How does an LX450 get to cambodia? I was under the impression they were only ever sold in US. I have seen some russians that buy all the exteriors pieces and "convert" their landcruiser. Interesting story

Old cars from the USA are routinely shipped over here. Sometimes they are cut into two pieces to avoid the high import taxes on whole cars. Then the chop shops here reassemble them and sell them. It's quite funny to see Cambodians driving around in cars that still have American bumper stickers on them when they have no idea what they mean (like "Texas A&M Mom", "KC BBQ", NRA stickers, and car dealer stickers) It's the wild west here... very hard to get parts unless you scavenge them off of other vehicles, almost no mechanics use any kind of shop manuals, and most of them don't know how to properly diagnose issues so they just start replacing parts until the problem goes away. My mechanic is better than most, but he definitely screwed up this time by missing the center transfer case issue and going for the transmission first. And I let my gloomy assumption that the slipping I was experiencing was probably the transmission clutch discs get in the way of insisting on a more rigorous troubleshooting process. I mean, neither me or the mechanic noticed that my AWD was only working as an RWD? Doh.

 

[98 SNAKE EATER]

Old cars from the USA are routinely shipped over here. Sometimes they are cut into two pieces to avoid the high import taxes on whole cars. Then the chop shops here reassemble them and sell them.

One of my customers does this for vehicles he picks up at the auction in Orlando.

He once had us disassemble a bunch of perfectly running Harleys and box up all the individual parts just so he could avoid the taxes.

Then he'd cobble everything together at his house in Thailand and sell them off months later.