So over a discussion about a better alternative to the 4 speed shifter slop problem with a machinist friend of mine we came up with an extremely simple, yet effective way to permanently rid the 4 speed of the slop.

 

What we noticed was that the original hole for the roll pin is 8mm. That's .3149". One popular method is to drill this out to 3/8 and install a bolt. Now - if you look at a tap/drill chart you will notice that the proper tap drill for 3/8 x 16 is 5/16" (.3125") for 75% thread engagement, or "Q" (.3320") for 50% thread engagement. This makes the original hole only slightly larger than a 75% thread engagement tap drill with 3/8 x 16 thread.

 

So I tapped the shifter and the rod (while still installed in the car) using a 3/8 x 16 tap. I tapped them together from underneath so the threads would perfectly line up. I then installed a grade 5 bolt (100% thread) from the top. You can get a box-end 9/16" wrench on the bolt if you rack the shifter all the way to the drivers side while you do it. I tightened this down, and then installed a 1/2 nut on the remaining bolt thread on the bottom as a locker.

 

I only had to remove the transmission exhaust support bracket to do the whole job. The slop is GONE from that portion of the linkage. I still have some from worn bushings and the bottom pivot bushing as they are shot. But even with those completely shot it's only around 2" of slop while in gear - not the crazy, bowl-of-oatmeal feel it had before.

 

This is a great alternative to the somewhat effective slop-fixes of old. It requires almost no dissasembly, and only a tap and hand tools. No drilling, cutting or other messy practices involved. Took me 30 minutes tops to make it happen.

 

I am fairly certain this will NEVER loosen. The reason is that once it's threaded, the whole mechanism is locked together by thread tension. The reason the original system, and the various "clamp" type systems eventually fail is because there is always a tiny bit of movement - this only gets larger over time. With it threaded it can never start to move, so it will not wear out. There just isn't any way for it to work loose with over 1" of threads holding it together.

 

Try it - you'll like it.

 

Here's a shot of it installed:

 

 

GD

Thanks for the info GD, I will probably be doing this soon.

Just be certain that you never rest your hand on the shifter as you drive down the road as this messes up the teflon slider pieces on the shifter fork rings.

 

I don't think the Japanese ever thought these cars would last this long.

Just be certain that you never rest your hand on the shifter as you drive down the road as this messes up the teflon slider pieces on the shifter fork rings.

 

An excelent reminder for the folks with 5 speeds. Sadly the fork slides on the 4 speed's are steel. I'm not sure what the effective difference is in functionality with the nylon vs. steel slides but I've never seen any wear on the 4 speed slides I've taken apart. Haven't pulled down a 5 speed with worn slides either but then I've only done a handful of 5's.

 

GD

also, the top of the bolt head that is towards the tranny case may need be filed so it does not hit the case. On mine, the bolt head hit the case enough to prevent hitting 4th and reverse easily.

 

And, all mine, the lower bushing and rubber sleeve is where the slop was, the roll pins were tight, it was the bushing that was the ENTIRE problem. I spent the time to tap out as listed above, and it was still slop, no better. Then i found the lower bushing MIA. I would have never had to tap that if i would have known.

The nylon donut's are usually gone, yes. But 95% of the time the slop is due primarily to the sleeve/rod interface. I haven't seen one yet that wasn't worn out.

 

GD

I just acquired another '86 Brat 4-speed dual range, and its current shifter is extremely sloppy bowl-of-oatmeal, not to mention it grinds 3rd gear.

This car came with an additional '84 4-speed dual range trans that is *supposedly* good.

 

 

I have in my possession the '83 and '86 Brat cars, extra 4-speed trans, and a 5-speed trans and everything to complete the swap.

 

I was now going to put the un-installed '84 4-speed into the '83 hoping the shifter is relatively tight and gears don't grind like has been claimed,

and i'm putting the 5-speed swap into the '86 (also hoping the trans i have doesn't grind gears).

[The current 4-speed manual in my '83 I drive is out of an '81 GL Wagon and it is a 4WD single-range only. Its shifter however is about the tightest feeling shifter in any 80's Subaru car I've ever driven. 2nd and 3rd gear syncros are shot though.]

 

 

I want to upgrade any fixes I can to fix shifter slop, if anyone has old pictures that were posted in this thread previously that would be nice.

Edited May 29, 201213 yr by TajMan

I'm kinda fond of the slop. Plus, it gives me a good excuse to tell people they cant drive it cause of the shifting issue.

I'm kinda fond of the slop. Plus, it gives me a good excuse to tell people they cant drive it cause of the shifting issue.

 

Haha! I use that exact excuse. Only a few people have driven my car since I have owned it. Although I hate the slop mines so bad I was forced to remove the plastic trim in order to shift. But im planning on the 5spd swap soon so I hope it shifts better.

Although I hate the slop mines so bad I was forced to remove the plastic trim in order to shift. But im planning on the 5spd swap soon so I hope it shifts better.

 

Now that's what I call dedication:clap:

Haha! I use that exact excuse. Only a few people have driven my car since I have owned it. Although I hate the slop mines so bad I was forced to remove the plastic trim in order to shift. But im planning on the 5spd swap soon so I hope it shifts better.

Damn and I though mine was bad. Shifting into 3rd and 4th is like shifting into 5th and 6th on any other vehicle, on mine. Still didn't have to remove the centerpiece in order to shift.