Builds Another Prado in Montana (2 Viewers)

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I popped the boot off the clutch fork the other day and noticed that the fork sits nearly all the way back in the opening in the bellhousing, causing it to chew a hole in the end of the boot, occasionally when it took too big of a bite the fork's travel would be limited and the clutch wouldn't depress all the way. Right now my plan is to grind some extra space in the bellhousing to allow the fork to travel farther, at some point if I have to drop the transmission for any reason I'll put a couple of washers under the clutch fork pivot to push it closer to the center of the hole. More info and photos of this here: LJ78 Clutch Issues - I'm Stumped! - https://forum.ih8mud.com/threads/lj78-clutch-issues-im-stumped.1259509/

The driveshaft vibrations have been plaguing me whenever I try to drive more than 90km/h, so I picked up a cheap angle finder and measured the output flange, driveshaft and pinion flange angles. The output and pinion flanges are parallel to each other at 3º each, so there's no problem there, but the driveshaft also sits at 3º, meaning that both u-joints have a 0º operating angle and therefore cause a lot of vibration. There's not a lot of info about minimum u-joint angles since it seems most people have trouble with too large of angles, but from what I've found they need at least a couple of degrees of operating angle. Based on the length of my driveshaft, it would take about 1.5-2" (38-50mm) in height change between the transfer case and rear axle to achieve this. I looked at putting blocks under the transmission and engine mounts, but the most I can get there is about 1/2" (13mm) before the transmission hits the tunnel. This leaves me with an unusual option: a 2" lift!

Unfortunately, my budget strongly advises against springing for a new set of lift springs, so I'm trying to figure out a cheaper way to achieve a lift until I can afford springs. I've heard that 80-series front springs fit in the rear on a Prado, but don't know how much lift, if any, they provide. I have also had a difficult time finding spring spacers that are a confirmed fit. Does anyone know what diameter the front and rear springs are?
 
I popped the boot off the clutch fork the other day and noticed that the fork sits nearly all the way back in the opening in the bellhousing, causing it to chew a hole in the end of the boot, occasionally when it took too big of a bite the fork's travel would be limited and the clutch wouldn't depress all the way. Right now my plan is to grind some extra space in the bellhousing to allow the fork to travel farther, at some point if I have to drop the transmission for any reason I'll put a couple of washers under the clutch fork pivot to push it closer to the center of the hole. More info and photos of this here: LJ78 Clutch Issues - I'm Stumped! - https://forum.ih8mud.com/threads/lj78-clutch-issues-im-stumped.1259509/

The driveshaft vibrations have been plaguing me whenever I try to drive more than 90km/h, so I picked up a cheap angle finder and measured the output flange, driveshaft and pinion flange angles. The output and pinion flanges are parallel to each other at 3º each, so there's no problem there, but the driveshaft also sits at 3º, meaning that both u-joints have a 0º operating angle and therefore cause a lot of vibration. There's not a lot of info about minimum u-joint angles since it seems most people have trouble with too large of angles, but from what I've found they need at least a couple of degrees of operating angle. Based on the length of my driveshaft, it would take about 1.5-2" (38-50mm) in height change between the transfer case and rear axle to achieve this. I looked at putting blocks under the transmission and engine mounts, but the most I can get there is about 1/2" (13mm) before the transmission hits the tunnel. This leaves me with an unusual option: a 2" lift!

Unfortunately, my budget strongly advises against springing for a new set of lift springs, so I'm trying to figure out a cheaper way to achieve a lift until I can afford springs. I've heard that 80-series front springs fit in the rear on a Prado, but don't know how much lift, if any, they provide. I have also had a difficult time finding spring spacers that are a confirmed fit. Does anyone know what diameter the front and rear springs are?

Here's a thread with info on the 80 front springs put into rear of an LJ78. LJ-78 lift using 80 series coils - https://forum.ih8mud.com/threads/lj-78-lift-using-80-series-coils.289092/ Sounds to me like they would work fine; if a little stiff.

I can confirm that spring spacers from Ebay Australia for the front coil sprung heavy duty 70 series fit fine into the front of an LJ78. I bought this brand and they worked fine: 2 Front Coil Spring 30mm Spacer suits Landcruiser 78 79 Series HZJ78 HZJ79 FZJ78 | eBay - https://www.ebay.com.au/itm/122376488930

Here are a 50mm version: 50MM Front Coil Spring Spacers For Toyota Landcruiser HZJ78 HZJ79 Series 2" Lift | eBay - https://www.ebay.com.au/itm/194237736769?hash=item2d3978a741:g:xyMAAOSwothg6~zg&frcectupt=true
 
Great info! I knew I had seen a thread about the 80-series springs but couldn't seem to find it. Perhaps 80-series front spacers would work with 78-series rear springs...
 
Not much has happened with the Prado recently, although I did have a fun odometer reading. (Apologies for the fuzzy photo)
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I also discovered that the clutch kit I purchased from LCEngineering now has a disclaimer on the website: Not Compatible With TDI Conversions. I've reached out to their tech support to see what about it is incompatible (it's rated for 300hp and 300lb-ft), but it looks like I may be in the market for a new clutch and pressure plate. :rolleyes: That would probably explain the shuddering in 1st and 2nd too. I have heard that the stock AISIN CTX107 pressure plate and DTX136 clutch disc are a good option, but I can't seem to find a torque rating for them and am not sure if they would be able to hold up to the ~275lb-ft my engine puts out.
 
Over the weekend I finally got around to replacing the clutch. I went with a Centerforce II kit for Toyota 5VZ-FE application; it's rated for 387ft-lb of torque, which should be enough... 🤔 The old clutch was definitely showing some wear, the little TDI wasn't too kind to it!
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Shiny new clutch and pressure plate:
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Installed!
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The new clutch feels worlds better than the old one. There's no chatter and engagement is very smooth. Unfortunately it didn't solve the issue with the clutch fork placement; the fork can still bottom out on the edge of the bellhousing, and the rubber boot still doesn't fit on.
 
While the transmission was out I took the opportunity to replace the factory breather on top of the transfer case with this nice little unit:
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It currently just has a length of hose attached to it and routed up on top of the transmission, but eventually it will get plumbed up into the engine bay along with the transmission and diff breathers.
 
I got in touch with the adapter plate manufacturer and found out that while the adapter kit they make is largely the same for 3.0 and 3.4 V6 applications, the 3.4 kit requires a special collar for the throwout bearing to push it closer to the pressure plate. Since I originally ordered a 3.0 V6 kit, I didn't get the collar. One is now on the way, I'm planning on installing it this weekend. Unfortunately that does require dropping the transmission again, but that will allow me to get the breathers all plumbed up much easier.
 
Finished installing the new throwout bearing today. The collar added by the adapter company adds about 1/4" to the length of the bearing. The clutch fork is now roughly centered in the opening in the bell housing, and both pedal action and shifting are smooth again.
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While it was all torn apart I noticed the transfer case shift linkage looked pretty sorry, so I gave it a quick bead blast and a coat of paint.
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A few weeks back I installed some OME rear springs and front spring spacers I got from @GTSSportCoupe. Unfortunately I neglected to take any measurements before removing the stock setup, but the lift is significant, especially in the rear. Presumably the stock rear springs were sagging a little under the constant weight of the rooftop tent and the OME's are a medium constant load, so I think I gained more than the usual 2" of lift. The front spacers are only 30mm, so it gives a little stinkbug stance. These photos were taken with a decent load in the back:
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Overall I am very pleased with the way it rides; the rear springs are a bit stiffer and reduce body roll. It handles a load very nicely. OME front coils are in the future, but other purchases are higher on the priority list. I still need to adjust the LSPV, as braking took a noticeable hit. Unfortunately the driveline vibrations are still present, but not as bad and mostly at higher speeds (95-115km/h). Currently looking into caster correction bushings or brackets for the rear axle to tilt the pinion down a bit, I haven't carefully measured the angles yet to see how much correction it needs.
 
In addition to the new throwout bearing, I also installed a new set of injectors this weekend. I had these rebuilt and digitally calibrated with Bosio DLC1019 nozzles by KermaTDI. The previous injectors had unknown brand 220um nozzles, these are 216um. Factory for these engines is 184um.

Here are the old injectors:
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Obviously there were some major issues with #2, and possibly #1.

New injectors ready to go in:
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Nearly there:
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Once up and running I took it for a test drive and was blown away by the difference! It was like driving a totally different vehicle. The next day I went on a slightly longer test drive: 300 miles from Whitefish, MT to Bozeman, MT. Here's a list of everything thats better:
- Lower EGT's. Maxxed out at 1125ºF pulling an 8% grade over the Rockies. Held 950º @ 110km/h and 1050º @ 120km/h.
- Smoother running engine, far less vibration, especially at low RPM
- Better low down power, I can now lug the engine like I'm used to with other TDI's (before I couldn't really use it below 2000rpm)
- Zero smoke, even under heavy acceleration
- Steadier holding boost, more gradual increase and less of a tendency to spike
- Quieter exhaust

There is less overall power, but I can now make full use of the skinny pedal when necessary. I checked Injected Quantity in the computer and it is up around 9.5mg/str, should be in the 3.5-6.0 range (lower numbers equate to more fuel) so I expect temps and power to increase some when I bring that back into spec, but still a massive improvement. Fuel economy looks like it has improved as well, but I haven't filled up yet so I don't know any numbers on that. With the exception of the driveline vibrations it felt quite happy cruising at 120km/h indicated (77mph according to GPS) on the interstate, so I really think I've got a great little highway cruiser here.
 
As weather has been getting colder recently my speedometer cable is inclined to grumble and squeal. Any suggestions for a preferred lubricant? I have had success using dry lubricants like powdered graphite on old air-cooled VW's, but have also read that injecting grease down the cable is a good idea. The issue doesn't seem to be covered in the FSM.
 
Took a little drive yesterday to enjoy the fall colors and explore some Forest Service roads in the area.
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The weather was a little different this morning:
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I had some time this afternoon so I tore into the dash in an attempt to lubricate the speedometer cable with some graphite powder. I haven't taken it for a test drive yet, so I don't know how successful it was. There isn't much of an opening in the end of the cable to put any kind of lubricant in. If that doesn't solve the problem I'll have to get more creative.
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I had some time this afternoon so I tore into the dash in an attempt to lubricate the speedometer cable with some graphite powder. I haven't taken it for a test drive yet, so I don't know how successful it was. There isn't much of an opening in the end of the cable to put any kind of lubricant in. If that doesn't solve the problem I'll have to get more creative.View attachment 2811827
Have you inspected the condition of the cable all the way back to the transmission? Mine had contacted the exhaust at some point and had rusty sheathing and was nearly crimped. I just bought a new cable... if there's obvious physical distress it may be worth your time to just replace the cable.
 
I had some time this afternoon so I tore into the dash in an attempt to lubricate the speedometer cable with some graphite powder. I haven't taken it for a test drive yet, so I don't know how successful it was. There isn't much of an opening in the end of the cable to put any kind of lubricant in. If that doesn't solve the problem I'll have to get more creative.View attachment 2811827

I was able to work some oil down into mine and it has been good since. It was years ago that I did it. I remember it being hard getting the oil into it - I may have pulled/pushed the cable around a bit to make a space. I think I just used a general purpose oil (3 in 1 or something like that). I definitely had to take some time and be patient with it.
 
I had some time this afternoon so I tore into the dash in an attempt to lubricate the speedometer cable with some graphite powder. I haven't taken it for a test drive yet, so I don't know how successful it was. There isn't much of an opening in the end of the cable to put any kind of lubricant in. If that doesn't solve the problem I'll have to get more creative.View attachment 2811827

I had unplugged it from the transfer case, pulled it all out from dash side, wiped it properly and greased it, flushed the casing with wd40 and compressed air and re-assembled. Worked quite well ever since.
 
I had unplugged it from the transfer case, pulled it all out from dash side, wiped it properly and greased it, flushed the casing with wd40 and compressed air and re-assembled. Worked quite well ever since.
That's probably what I'll end up doing eventually, the noise has only just started and is quite mild, so hopefully I can get this cable to last a while yet.
 
Have you inspected the condition of the cable all the way back to the transmission? Mine had contacted the exhaust at some point and had rusty sheathing and was nearly crimped. I just bought a new cable... if there's obvious physical distress it may be worth your time to just replace the cable.
I haven't given it a good inspection yet, but a couple of weeks ago when I had the transmission out there was no obvious damage.
 
When I bought the Prado it only came with one key. I finally got around to ordering a 90999-00085 and taking it to a local locksmith. Now I have a spare!
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New look on the front end! Still have to properly bolt it on, there are just three bolts per side instead of five. I also need to get a roller fairlead for the winch. Overall very happy with the way it turned out though.
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Q: You Just welded extensions to the frame.. drilling extra holes for the bolt.. did you have to cut the wings.. and if so.. how Much.
I have the short cab with removable fiberglass top.. same front.
 

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