• FREE SPEECH SOCIAL MEDIA

    If you're looking for a Free Speech Social Media site, check out Blabbook.com

    - NO FACT CHECKING - NO SHADOW BANNING - NO POINT OF VIEW CENSORSHIP

Powertrain Woes on 86 toyota

tbplus10

Moderator
Staff member
1000 Posts
Community Leader
The last one I did was in the field and we made a choke collar that we tightened behind the race and it was forced off.
 

old truck

New Member
I don't guess I know what a "choke collar" is. Are you talking about the race on the shaft or the one in the carrier?

I got the cup race out with fairly light tapping with a punch, working steadily around the race. I tried heat on the cone race but it wouldn't let go. I have the pinion shaft in the freezer and will try heat on the cone again tomorrow.

I got the number off the cup and found the cone number online at: http://www.gearinstalls.com/bearing.htm. This bearing is a KOYO TR0708-1r-N cone/TR0708-1-N cup.
 

old truck

New Member
I think I found out what a choke collar is today. It was part of a big Proto puller set that grabbed on behind the race. I had pulled the shaft out of the freezer and driven 3 miles with it wrapped in a towel to keep in the cold. We tightened the puller so tight that the bolts holding the collar together were quite bowed. We put heat on the cone and hit the puller screw. Nothing showed any sign of moving. I told the guy not to break his tool for me and we gave up. The cup race had spun in the carrier. I am assuming that the cone race spun on the pinion shaft and galled it up. It's going to take bigger tackle to land this one.
 

toyotafan

Toyota Truck Club Founder
Staff member
1000 Posts
Just passing by tonight and looking at your pics, looks like this is a project you're dedicated to getting done before winter hits. Keep at it, looking good.
 

old truck

New Member
I found the name of the tool we tried and failed with was a "bearing separator." It was indeed going to fail before that cone race moved down that shaft.

I was advised yesterday to try to break the race with a chisel. That was not working well either, and my hands took quite a beating in the attempt. I took an angle grinder and just started cutting away as much of the race as I dared, avoiding hitting the pinion or shaft. After a couple of hours, I got it thinned down and to crack with the chisel and was able to slide the broken race off.

What I had assumed above was, in fact, the case. The race had spun on the shaft and galled the surfaces, pretty much welding it on there. I can confirm the Koyo numbers for both races, and will have to make a trip to the city to hit up the bearing supplier.

My dummy diff is working fine to allow me to have the truck operate as a 2WD. I have some road miles on it and it is serving well.
 
Last edited:

tbplus10

Moderator
Staff member
1000 Posts
Community Leader
Theres a couple different version bearing separators available, the choke collar style I keep in my truck box is wedge shaped and has bolts on either side to tighten and force the bearing off. Mine is a heavy cast item and was originally designed to remove props from ships, its rated at 35tons so Ive never worried about breaking it.
Most times if they get galled or sparred on the shaft the only option is cutting or chiseling.
I'd love to see a pic of your dummy diff, sounds like the design shows promise.
 

old truck

New Member
The guy used the collar-like Proto with a puller that hooked the outside edges. If he'd had the bolts it was set up to take, I think it would have had a better chance. As it was, those two bolts that pulled it together were bowing dangerously. I saw that tool in a Proto set online selling for $645. I'm glad we called it before something gave out.

After lunch today, I couldn't grip anything after all the banging on the chisel.

The heart of the original construction of the dummy diff was my makeshift slide hammer. It was a leftover 2X4 stake pocket from a trailer I'd built, and part of the handle off an ancient lawn roller. The bar from the handle offered a place to hit with a two pound hammer and the rectangular tube just spanned two of the studs on the axle flanges.

Since that span was the same as the holes in the drive shaft flanges, I thought I could use it again for the dummy diff. As it turned out, by welding a 2X2 tube to the other end, the span was perfect. I added four washers to each of the bolts between the two tubes and the drive shaft end flanges to protect the protruding CV joint covers. I slipped a 1.5 inch square tube inside the 2X4 tube to catch a bolt from right rear shock mount bracket to support the rear side of the crazy lash-up. I used one of the shock mount bolts, double nutted to the front bracket to provide the main support angle iron scrap.

Pics of the dummy diff (in the order they posted):
Whole thing from the rear.
Right side from the rear.
Right side from the front.
Left side from the front.

IMG_1200.JPG
IMG_1195.JPG
IMG_1194.JPG
IMG_1193.JPG
 
Last edited:

old truck

New Member
Not the prettiest but looks to do the job.
From the scrap iron pile, all of it. Being as how I'm not a pro in a shop, hopefully this will be used only once for my needs. I will be happy to return it to the scrap pile to wait for its next incarnation.

After almost 30 years of wheeling these trucks with some of the smartest Toyota techs around I've yet to see one come up with a good work around this problem.
You might submit this:

If I were fabricating one, I would have simply used a piece of square tube, nearly the length of the diff and axles, from flange to flange. The ends would simply be flat bar, doubled at the ends for clearance of those CV joint cover plates on the ends of the drive shafts, and with two studs for bolting them up to the drive shaft flanges. Add a couple of braces to the shock mount brackets, and there you have the sanitary version, ready for painting. Hang it on the shop wall until needed. I'll be waiting to hear the patent number. Call it, "The Dummy Diff," and say you named it after me. :)
 
Last edited:

tbplus10

Moderator
Staff member
1000 Posts
Community Leader
The advantage yours has is locking hubs, for some reason a lot of guys either cant find locking hub conversion kits or are to lazy to do the conversion.
With the auto hub set up the axles still turn, gotta find some way to acomadate the spinning half shafts.
 

old truck

New Member
I got the new bearing in and the diff is back on the job. There's another issue now. I heard bad noises when I was stuck in 4WD on that steep driveway, trying to get it into 2WD. I am thinking I broke a tooth off a gear in the transfer case. When I had it in 4WD, it did okay under a light load, but it bumped and clunked when the load increased when going up a slight incline. Once, when backing slowly, it grabbed hard and stopped. I hit the clutch as fast as I could when that happened. I have unlocked the hubs and have been in 2WD since.

So, question, is an '87 transfer case the same as an '86? I may have a line on a possible parts rig.
 

tbplus10

Moderator
Staff member
1000 Posts
Community Leader
Yes 86, 87, and 88 shared transfer cases.
Theres something about the auto hubs Im trying to remember, I dont remember it being important, ie it was something that could be worked around easily to make everything work correctly.
I'll ask around in case you parts truck has auto hubs.
 

old truck

New Member
I found a web page that said there are two forms of transfer cases: top shift and forward shift. The top shift it says in trucks with bucket seats and the forward shift is in the bench seat models. The '87 junker/project truck I'm going to see has buckets but it comes with an extra trans and transfer case. I talked to the guy and he said the spare is forward shift. My truck used to be a bench and I'm pretty sure it is a forward shift.

I'm going quite a distance to see the truck tomorrow, but I will be most of the way on another mission as it happens. It has a bobbed frame and no engine. So, it's basically, the power train stuff and a project I have no interest in getting into. The guy is moving for a job a long way off and is abandoning his project. He's asking $500 for it.

My truck has locking hubs.

 

old truck

New Member
Here I am, back after almost 4 years, 20 pounds lighter and now past 70 (turned 71 two weeks ago), coming back from a Lyme's disease diagnosis. Had one pretty bad year, but with a Chinese medicine specialist naturopath, not doing too badly now.

Still no four wheel drive, but I am determined to get that taken care of. I got a forward shift transfer case off Craigslist before I got sick, and it's ready and waiting to get in there. Other issues that will need seeing to are a leaking front seal, leaking rear axle bearing seal, and a leaking exhaust manifold gasket.

I have found videos for those other three issues and am not too afraid to go at them when the weather settles some (still no shop to work in). My "usual" helper has long gone his way, so I may have to get someone to help with some lifting, if I can't just remove and replace the T-case on a floor jack. What I need to know is what to know about replacing that T-case with its forward shift with the tranny still in the truck. Is it doable, or does the trans have to come out? Any tricks and/or things to look out for?
 

jazz

Mechanic
100 Posts
I can't help you but good to see you are back at. You might try Yotatech for your answers. I'm just not familiar with these but if the transfer case bolt pattern is the same no reason it should not work. I would want to know for sure before tackling this if any issue could arise.
 

Related Content You Might Like:

Top