7 replies to this topic

[GermanMoreno]

Hello! I have recently have the car slipping out of 4th gear whenever I get out of the motorway. The turn is really large, meaning not a sharp turn. The type of turn that pushes you by inertia to the opposite side you are turning. If its more than 5seconds or so, the 4th slips out.
Sometimes it also happens after a long straight line drive (more than an hour or so) cruising at highway speeds 120kmh or more.

I assume this is because of vibration? Maybe mounts? I wanted to know where I can start troubleshooting.

Points to consider:

- I have installed a KAD shortshifter and also a gearbox bias barrel slick shift from minispares.
- Steering rack was recently changed and the subframe was dropped.
- All other gears stay engaged.
- when i release the gas pedal I feel a jerking that occurs maybe a split second after. Like 1 push pull from front to back, hard to explain, almost like i was bumped from behind not very hard.

Any ideas are greatly appreciated!

PS: I bought lower gearbox stabilizers Left and right, and I will check engine mounts. I feel like something might be loose and the turn/vibrations are causing some play making the gear slip out.





 

[Designer]

Hi,

 

I have no knowledge on short shifters or their fitting. I have a standard rod change on a 1988 Mini.

Did you replace your rod change oil seal gaiter?

When I was experiencing dropping out of second, fourth and reverse gears I discovered that the new part number DAM3022 (purchased from Minispares) that I fitted was not to the correct spec. 

It was about 3mm longer and the rubber was harder so not so easy to compress. This meant that the selector rod (if that is the correct term) was not being pushed far enough into the gear box therefore not engaging those gears fully.

In second and fourth while moving at a constant speed no problem but as soon as a change of speed or cornering out it would pop. In reverse it would pop out of gear just after releasing the clutch and moving about four or five yards.

I still had the old gaiter( still in acceptable condition)so refitted it and no problems since.

As you have a bias barrel slick shift it may be why you are only experiencing this problem in fourth gear.

 

Paddy

Edited by Designer, 17 May 2025 - 06:59 AM.

[Steam]

If you can rock the engine back nd forth by hand (may need a bit of effort though) then it may be the reason. Also if you rev the engine look to see if it moves back and forth on its own. That would indicate engine steadies worn or loose which will pull on the shifter and can pull it out of 2nd, 4th and reverse. You may not have noticed 2 & R but you're not in those gears long enough to affect it.
You may want to temporarily change out the slick shift and the quickshift to see if it fixes it aswell.

[Spider]

If you have the short rubber bellows fitted, that Paddy mentioned, cut it off. They do more harm than good. They usually don't allow 2nd, 4th and Reverse to be fully selected.

If it slips out of gear a few times under power or over run, and it doesn't take many it will round off the dogs on the gear itself and then it'll never hold gear.

[1314cc]

As Designer mentions, I also had to cut down oil seal rod gaiter to stop the jumping out of gear

[GermanMoreno]

Yea I had changed that gaiter when fixing the oils seal. I’m gonna inspect. Thanks for the advice!

[Spider]

Yea I had changed that gaiter when fixing the oils seal. I’m gonna inspect. Thanks for the advice!

 

The early cars never had the gaiter and looking at how the fit up and what happens as you shift through the gears, all I see them doing is holding road dirt etc all nicely so that when you select 2nd, 4th and Reverse, the Shifter Coupling can then perfectly shove that dirt and grime in to the seal.

I'm not sure if you have ever read where I go (literally hell and high water), I've never run these bellows and never ever likely to either !

[Ethel]

I've never seen a bellows fitted that wouldn't be an MoT failure is it was on the steering.