Notes on replacing steering shaft firewall boot (2 Viewers)

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I personally don’t find it very difficult or time consuming to change the firewall seal. It’s under an hour job unless the lower splines are rusted badly on the shaft at the box.

Cheers
 
I had an idea and ran with it. Its been doing good so far probably 6 or 7 trips and 3000 km or so since I did this. I originally posted on a fb group but now I have had it longer and a few other guys have tried it with success.

From day one I always felt the 80 had a dead spot in the steering. You really noticed it when there were grooves in the road. You would chase the steering back and forth trying to keep it straight. I started to look at what the hell was going on. First I checked all my bushings and tie rods. Replaced tie rods and track bar bushings because they looked to be original. Issue persisted. I noticed when tires were on the ground and you dry steer the steering shaft coming through the firewall moved up and down like it was bent. Upon further investigation I noticed u joint to rag joint to another u joint right before the steering shaft goes through the firewall on the inside. When you try to steer that rag joint would torque up or down and you could feel the play before the wheel started to move. So I went down the mud rabbit hole and found a couple things.
1-find your feet get hot or it stinks in the cab of hot motor? The rubber seal that rides the steering shaft is probably gone leaving a hole right at your feet.
2-there is an adjustment nut on the steering box to take up slack.
3-there is an adjustment at the tilt steering mechanism that allows you to remove up and down play of your steering wheel.
4- the only way to stop that rag joint from moving around was to add a bearing. This also greatly increases the life span of the bushing.
Now lots of people had tried the bearing technique and complained about it squeaking and it drove them nuts. So I thought about it and came up with a system that so far has worked flawless. After going through these 4 items I have no dead spot and it's nice and responsive without a squeak.
1- get a new rubber seal from Toyota along with the rag joint. I got my rag joint off rock auto because I'm a cheap.
2-order a steering shaft support bearing off ebay 20mm or 3/4"
3-get a pack of these springs, 2 m6x60 bolts, 4 m6 nuts, 6 m6 washers, 6 m8 washers, a peice of thick shink tube that fits over the bolt.
4- lay it all out on the bench
5- crack beer
6- climb under your dash abd remove the old rag joint and slide the old seal off the shaft.
7- cut two springs in half. And this part is a bit specific to your bolt. I used a 50mm bolt but I wish I had 60mm it would give more clearance to the fire wall.
8- Slide m6 washer onto each bolt.
9- Cut shrink tube to just longer than the part of the bolt without thread. Heat it up and shrink to to the bolt.
9- Slide one half of the spring on followed my a m8 washer. Do this for both bolts.
10- Now slide the bearing assembly onto the bolts then another m8 washer spring then m6 washer. Put one nut on the bolt and tighten it until it bottoms out the thread. You not have floating bearing assembly. That has the ability to move with the shaft and wont squeak.
11- Install a second nut, you may want to get a couple extra nuts and use them to take up any extra thread so nothing can come loose. Leave enough thread that there is 15mm or so past the new seal or so to be able to re bolt to the fire wall. Don't forget the washer infront of the seal!
12- Climb under the dash and slide the assembly downtown the fire wall and tighten the bolts up. Then tighten the set screws onto other shaft.
13- Have another beer, you have been doing yoga for 15 minutes under the dash you deserve it.
14- Now the hardest part I found was getting the new rag joint back in. Sliding it over the shaft is simple but getting the steering column side to line up again was hard. I ended up getting a hand and unbolted the column, pulling it back ever so slightly to get the bolts in.
14- Once installed make sure you tighten everything up! It's your steering double check!
15- Take it for a drive and feel the difference.
Mine has been this way for 3 offroad trips now and no squeaking of any sort. Steering still feels nice and tight. So I figured it was time to share.
Hope this helps some one out! See you guys on the trail!

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15 minute job tops to replace the firewall steering shaft seal as the OP and @LandCruiserPhil have described. Any 80 in use in the territory of the Common Krait or other similar nasty creatures should have this repair effected.
 
15 minute job tops to replace the firewall steering shaft seal as the OP and @LandCruiserPhil have described. Any 80 in use in the territory of the Common Krait or other similar nasty creatures should have this repair effected.
Please take a real time video of you doing this in 15 minutes. I would like to see it.
 
Safe to say that I was overdue for a new seal. 🤣

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FWIW I once asked a manufacturer of rubber/polyurethane parts if they could
make up a replacement shaft seal but with a thicker possibly longer lasting polyurethane or silicone rubber. They said no problem, except that the cost would be very high so I dropped the idea. Maybe a MUD vendor who could order in bulk would be interested (@NLXTACY ), but then again the OEM seal is inexpensive, so IDK.
 
Sometime soon here I plan on just cutting out a new one from a piece of UHMW, I just don't have a 3/4" drill bit handy and all my pieces are too thick for a step bit.
It will seal it pretty well, support it so you don't get the added slop of having 3 flexible joints in a shaft, and not squeak/squeal because it's just as slippery going in and out as it is when rotating.


For those worried about the body flexing:
Try moving the long shaft up and down, at the firewall. Notice that the 2 joints on the inside allow it to do so without any binding.
So binding is not the issue. What is an issue is a 2 segment driveshaft with all flexible joints and no carrier bearing.

I'm guessing Toyota did it with the rag joint to make the steering softer (and more luxurious?) by allowing the rag joint be a 2 stage spring- it lets it twist out of alignment (and exert force onto the bellows seal) which would result in less twisting/impulses on the steering wheel when driving on rough roads.

Of course, the rag joint already has that springing ability because it's rubber. But with the unsupported shaft they use its resistance to flexing (which is pretty weak) rather than its resistance to torsional forces (which is very stiff). So they basically get a 2 stage spring in that steering impulse softening effect.

Effectively they gave it a larger "suggestibility" zone before it really acts hard on the wheel, which is presumably desirable on rough roads because fewer of those impulses will reach the wheel with any real strength behind them, giving greater driver comfort and less fatigue on really bad roads.


In windy mountain pass and highway conditions on the other hand, it just kind of sucks.
I will be removing that effect because I want more precise steering. With the bushing rather than the bellows It will be straight to the torsional stiffness of the rag joint, and probably cut down the suggestibility zone by a lot.
 
Just did mine this weekend. Had to remove the 4 bolts as well to get the plate off completely since my old seal would not come loose after 30 yrs. I am pretty sure it was the original seal.
 
Wonder if someone with a 3D printer could make up a longer lasting but still flexible seal??

 
Wonder if someone with a 3D printer could make up a longer lasting but still flexible seal??

why? it takes the most 15 mins to remove the 3 bolts on the shaft coupler and 2 bolts for the seal.
 
why? it takes the most 15 mins to remove the 3 bolts on the shaft coupler and 2 bolts for the seal.
I will state it again.

Please post a real time video of you changing this seal in 15 minutes. I would like to see it done.
 
I will state it again.

Please post a real time video of you changing this seal in 15 minutes. I would like to see it done.
you want to buy me a beer if i post one? I had to remove the 4 bolts to get the plate off and hammered the crap out of the original seal. But it will take less than 15mins now that am to replace that again.....
 
you want to buy me a beer if i post one? I had to remove the 4 bolts to get the plate off and hammered the crap out of the original seal. But it will take less than 15mins now that am to replace that again.....
From the time you get out of the truck after driving into the garage, until you are finished putting away tools, it's more than 15 minutes.

With no tools laid out ahead of time or or "pre-preparation", then clean off tools and put away in the tool box again, I would love to see it.

I will buy you a beer next time I'm out your way or if you come my way.

Prove it. 😁
 
From the time you get out of the truck after driving into the garage, until you are finished putting away tools, it's more than 15 minutes.

With no tools laid out ahead of time or or "pre-preparation", then clean off tools and put away in the tool box again, I would love to see it.

I will buy you a beer next time I'm out your way or if you come my way.

Prove it. 😁
Well I guess so, but with all the right tools, couple sockets and wrench, 5 bolts to remove and install, not really time consuming, I will post a video if I have free time to spare. A 1/2 🍌job :)
 
Well I guess so, but with all the right tools, couple sockets and wrench, 5 bolts to remove and install, not really time consuming, I will post a video if I have free time to spare. A 1/2 🍌job :)
You can wait until it's time to replace it again.......


I may even spring for two beers if I'm feeling generous!


My real point is that a first timer doing this will be way more and depending on what else you run into (rust, missing hardware, broken hardware, parts needed) will always blow the time.

You don't know what tools you need, how many parts to remove, etc.

A video would certainly help all the newbies.
 
You can wait until it's time to replace it again.......


I may even spring for two beers if I'm feeling generous!


My real point is that a first timer doing this will be way more and depending on what else you run into (rust, missing hardware, broken hardware, parts needed) will always blow the time.

You don't know what tools you need, how many parts to remove, etc.

A video would certainly help all the newbies.
Deal...I agree, my time of 15 mins is generous, but not for 1st timer or newbies..it took me much longer with my seal fused to the plate it was attached to, so had to remove that and hammer the old seal out. But the shaft collar removal is straight forward.
 
IME the pain in the arse part is trying to fit/bend/reach/work in the foot well. If I didn't have to do that again for another 20 years (with a more durable seal) I'd be happy.
 
IME the pain in the arse part is trying to fit/bend/reach/work in the foot well. If I didn't have to do that again for another 20 years (with a more durable seal) I'd be happy.
I ended up removing the driver's seat, the lower dash and crash plate to get to mine.

I also changed my rag joint while I was in there, then added a CDL switch and did the pin 7 mod, and removed the RS3000 alarm system.
 
Yeah, I'll remove the seat next time.
 
Thanks for the write up. Replaced my seal today with no drama. I tried to keep it under 15 minutes, but failed miserably. Closer to an hour for my skills.
 

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