Your rear shift rod is suspended inside the shift tube by, depending on year, either two or three bushings that clip onto the rod, and hold the rod suspended in the center of the tube. All of the weight of the shift rod is borne by these springy bushings that look like badminton shuttlecocks. This means that the rod never actually touches this inside of the shift tube, a concept that took me a little while to wrap my head around.
That means that the only portions of the shift rod that need to be lubricated are JUST the bushings. Not the rod itself, and not the tube. Just the bushings. If you are replacing these bushings, be aware that the reproduction units are not a good fit, and will likely require trimming of the pegs that latch into the shift rod and hold the bushing in place.
The more overlooked item is the tube itself. Here's the relevant diagram:
You'll see that the shift rod is actually two parts: a front section (#10) and the rear section (#12-#14.) The front section is protected by the steel pan that protects all of the mechanisms under the floor of the cab. The rear shift rod is protected by a tube (not shown) and the front and rear ends of the tube are sealed with a boot (#14, on each end) that allows the rod to move the 3 inches or so of throw through the tube without letting grit in.
Unfortunately, the front boot failed. So any bit of grit, dirt, salt, water, or road goo that happened to hit the boot wound up inside the tube, there to get trapped in the bushing lubricant and start grinding the inside of the tube and the bushing into a tarry, crunchy sludge. The same for the socketed part of the front shift rod (#10 that looks like the resonator on a kazoo. (Or the bowl of a hash pipe; pick your own analogy.) The shifter ball (#3) goes down in here and seems to attract the worst road grit imaginable.
So everything had to come out. #14 requires engine and transmission removed to be removed. #10 does not. I cleaned compulsively with degreaser, but some of this was no longer grease--it had almost turned to clay. Much scraping, even with a pick ensued. Then the whole of both rods were liberally degreased again and many shop towels permanently wrecked. When the rods were as clean as can be expected short of heaven, I coated them in a light anticorrosive, snapped the bushings back into place, and then added
Coastal Premium Hi-Temp Grease into each of the bushings of the rear tube with a syringe. (Why a syringe? Because these bushings were now cleaner than they had been in 37 years when they were first installed. And I wanted to keep them that way, especially by keeping the grease tucked inside and just around the bushing and not giving the whole thing a bath when all it needed was a grease job.)
There was another source of contaminant though: Inside the shift rod TUBE itself. All of the grit and goo still stuck in there...yeck. The tube is a steel pipe about 1 inch in diameter. I sprayed Oil Eater brand cleaner up inside the tube, then used a five foot length of 3/4" PVC pipe as a ramrod to cram wadded paper towel down the tube. After half a dozen passes, the paper towel stopped coming out of the front of the pipe looking like it had been dragged through a sewer. Time to pull out the big guns: Brake cleaner.
Brake Cleaner is great for stuff like this, because it cuts through grease like you wouldn't believe when it is wet. But it flashes off (evaporates) so fast that it doesn't have time to do damage to raw steel. You also don't want to inhale this stuff, either. Well ventilated. I filled the tube with a liberal dose, and then performed my ramrod procedure with clean towels. I got an extra level of clean from the Brake Cleaner, and now the tube was as clean as it could get.
I stuffed the shift rod back into the tube, taking off the grit covers (plastic sandwich bags) as I went. Finally, the shift rod was well seated. back in the tube, I put on the new boot at the front, went to put on the rear one....and was stymied. Believe it or not, the assemblers apparently expected you to snap each of these bushings into place and lube them WHILE you were loading the rod. Because there is no other way that the rear boot can be installed without splitting it. Which quite negates the purpose of having a seal that permits the rod to move in and out of a set of bellows to work the transmission. I'll review this later, but I'll need to find some other solution. That rear shift rod is not coming back out.
The front rod (And the shifter ball #3, and the reverse lockout spring #5 was filthy, gritty, etc. Frankly, I'm amazed that the thing shifted at all. Then I discovered that there was a part missing and just about fell into hysterics under the bus.
Part #15 in the diagram at the top of this page is a bushing which holds the front the shift rod inside a it and keeps it stable. This bushing was a remarkably tough nut to get into the receiving hole: I eventually put it in boiling water for 5 minutes to soften it, and even then my fingertips came away bruised. The bushing has an internal groove to store lubrication so after finally getting it mounted, I lubed up the front end of the 'hash pipe' and slid it in, neat as you please. Just like they wuz made for each other.
So now the real fun begins. With the shift mechanisms, bushings and other consumables all sorted, the transmission can go back in, the CV joints cleaned and repacked (I'm told that this is like wrestling a sow) and then the inboard CVs reconnected to the transmission. Finally, reconnect clutch cable to throw out arm. Then spend an hour adjusting the shift gate until all five gears (1-4 + R) happily click right into position.
Why did this take so long? Blame the rain, snow, cold, and my job, all of which conspire to keep me away from these simple, not actually very time consuming tasks!
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| Front shift rod in place with new bushing and lubrication, awaiting installation of shifter from above. |
Unfortunately, the front boot failed. So any bit of grit, dirt, salt, water, or road goo that happened to hit the boot wound up inside the tube, there to get trapped in the bushing lubricant and start grinding the inside of the tube and the bushing into a tarry, crunchy sludge. The same for the socketed part of the front shift rod (#10 that looks like the resonator on a kazoo. (Or the bowl of a hash pipe; pick your own analogy.) The shifter ball (#3) goes down in here and seems to attract the worst road grit imaginable.
 |
| Why a syringe? Because when you're delivering this goop only to specific fittings, its best to have some control over getting it there. |
Coastal Premium Hi-Temp Grease into each of the bushings of the rear tube with a syringe. (Why a syringe? Because these bushings were now cleaner than they had been in 37 years when they were first installed. And I wanted to keep them that way, especially by keeping the grease tucked inside and just around the bushing and not giving the whole thing a bath when all it needed was a grease job.)
There was another source of contaminant though: Inside the shift rod TUBE itself. All of the grit and goo still stuck in there...yeck. The tube is a steel pipe about 1 inch in diameter. I sprayed Oil Eater brand cleaner up inside the tube, then used a five foot length of 3/4" PVC pipe as a ramrod to cram wadded paper towel down the tube. After half a dozen passes, the paper towel stopped coming out of the front of the pipe looking like it had been dragged through a sewer. Time to pull out the big guns: Brake cleaner.
 |
| A thoroughly cleaned original bushing being re-installed on the shift rod. Note that the lithium impregnated lube is only on the shift rod itself. The body of the rod has been sprayed with an anti-corrosive. |
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| The bright flecks of gloss you see are not the wavy surface of the grease reflecting the flash. They are the tiny, tiny bits of grit, sand, dirt, and assorted contaminates reflecting the flash! The whole assembly got a heavy duty degreasing and will get lubed with the same grease the rest of the linkage is wearing. |
I stuffed the shift rod back into the tube, taking off the grit covers (plastic sandwich bags) as I went. Finally, the shift rod was well seated. back in the tube, I put on the new boot at the front, went to put on the rear one....and was stymied. Believe it or not, the assemblers apparently expected you to snap each of these bushings into place and lube them WHILE you were loading the rod. Because there is no other way that the rear boot can be installed without splitting it. Which quite negates the purpose of having a seal that permits the rod to move in and out of a set of bellows to work the transmission. I'll review this later, but I'll need to find some other solution. That rear shift rod is not coming back out.
The front rod (And the shifter ball #3, and the reverse lockout spring #5 was filthy, gritty, etc. Frankly, I'm amazed that the thing shifted at all. Then I discovered that there was a part missing and just about fell into hysterics under the bus.
 |
| Cleaner! |
So now the real fun begins. With the shift mechanisms, bushings and other consumables all sorted, the transmission can go back in, the CV joints cleaned and repacked (I'm told that this is like wrestling a sow) and then the inboard CVs reconnected to the transmission. Finally, reconnect clutch cable to throw out arm. Then spend an hour adjusting the shift gate until all five gears (1-4 + R) happily click right into position.
Why did this take so long? Blame the rain, snow, cold, and my job, all of which conspire to keep me away from these simple, not actually very time consuming tasks!
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