Inappropriate Downshifting

[Stiful]

G'day again.. If the OD switch is faulty, the usual cause is a physical break within the switch itself which stops it from staying in position when pressed in.
What happens is there is a small spring inside the switch. It is the kind of spring that is shaped like a cloths peg. One side of that spring breaks free of the bit of plastic that retains it so that the switch locking down mechanism wont engage.
You can either replace the switch/arm assembly or pull the switch apart and put a very small tin plate in to repair the split plastic one. Mine arrived with a broken OD switch and I fixed it and documented the fix somewhere on our site. The fix is permanent and has been used by many people. It will outlast a replacement switch..
Some people tape it down. Some people have even been known to put nails and things down the side to keep the button pushed. It is always switch related and not the transmission . Unless 4x4ing , leave it in OD all the time. The gearbox will sort it out. Remember the OD light only comes on as a warning when the OD is OFF .. Cheers.

[delicabits]

if the od is playing up just change it as they arent expensive to replace.

[djelica]

Hi Everyone,

Well I thought this problem was a thing of the past as it didn't happen on my last trip to and from the Kootenays, but it was very bad today when I drove to Edmonton and back (from Calgary). Downshifting and not refinding top gear for a long time. It was like the O/D was switching off but the "OD OFF" light never came on, so I don't think its the switch (unless the O/D can be off without this light being on then I will look at he switch and wires in the shifter).

The only thing I have done in the past was to disconnect the battery for about a half hour to clear the "memory" of the transmission "brain". This seemed to work as the problem was gone for some time, but that may just be coincidence. Now I know this is not fixed I will go back and look into the TPS and kickdown cable solutions, but my gut tells me that these are not the problem. The machine shifts fine, up and down right around 2000 rpms and the downshifting happens on flat stretches of road with my foot stationary on the pedal at around 100 to 110kph. No movement of the accelerator at all and very consistent speed, so can the kick down cable be the cause? I will look into these things as I search for a solution but I want to explore all the possibilities and go through them in a logical order.

So, I've done some more searching and I have found some posts on other sites that suggest that the problem may be with the gearbox temperature sensor. Some were having problems with the sensor and condensation and such and I was wondering if anyone can tell me where this sensor is located on the L400? How is it checked or is it best to just replace it? Could it also be a faulty switch right on the gear box?

Also where is the transmission filter. The fluid looks really clean and I know it was changed when it arrived in Canada, but I might change the fluid and filter as I am not sure if the filter was replaced or cleaned at that time. One other thing. When I checked the trans fluid it seems a bit high. Could too much fluid be causing this problem?

OK, that about enough from me on this for tonight. Thanks to anyone who can help. Cheers, Darren

[djelica]

I over-rode (is that a word?) the A/T temp sensor as per

http://www.pocuk.com/forums/viewtopic.p ... t=earthing

I've been on the highway three times since and have not experienced an inappropriate gear drop since.
It's only been a few times and this may not be the fix, but I have some big drives ahead in the near future and will update this post as need be.

For the record I checked the TPS and it was .8 (close enough to the .78 that I have read to be a good number so I left it alone) and I have done nothing to the drop down cable. The other possibilities as I recall are dirty A/T fluid (seems clean) and a clogged filter (haven't checked as I haven't figured it out yet).

Anyway, the way it was acting was very much like a short as the OD would go on and off at completely random times and I think the sensor may be it. Hope I'm right.

Now I have a clunk in the rear (driver side it seems) when the suspension is unloaded. It doesn't happen all the time but the rebound from a bump will get a very subtle clunk from the driver's rear every once in awhile. And it is worse when I turn right and the front passenger drops into the turn and the driver's rear goes up as the load shifts. The turn into my alley is a right turn and going down a pretty steep hill. I have to brake just before turning and this really loads the front end and as I turn the driver's rear is really unweighted and the clunk is pretty loud. More of a clunk CLUNK clunk.

I have found this (and other posts about torquing down subframe bolts that I will do)

http://www.mdocuk.co.uk/forums/viewtopi ... de56dcdf34

I know this post talks about a passenger side clunk but I was still wondering if anyone knows where the rear brake load sensinig valve is.

Thanks for any help, djelica

[jessef]

The clunking in the rear is most likely your shocks topping/bottoming out.

If the shocks are toast, you'll get some good clunking going on back there.

Things to check would be your exhaust too. It can make a rattle/clunk sound at the hangers but what you're describing sounds like the shocks either topping out (stretched too far) or the bushings in the shock mounts are gone = clunking.

[djelica]

Thanks Jesse,

I'm sure the shocks are original as it has the ECS system and I see that these shocks are plugged in to the system, so I'm sure they are 15 years old.

I was under it twice now checking exhaust (seems solid) and checking suspension bolts (nothing loose), and I did tighten the rear hatch bolts and spare tire, but it still happens.

Looks like new shocks may be in order. I think I saw a thread on replacing ECS shocks and that it was pretty expensive and that an after market (normal) shock would be a good choice. Any advice?

Thanks in advance, Darren

[Green1]

Looks like new shocks may be in order. I think I saw a thread on replacing ECS shocks and that it was pretty expensive and that an after market (normal) shock would be a good choice. Any advice?

Near as I can tell, the difference between "sport" and "touring" mode on the ECS is very little, as such, I certainly wouldn't be willing to spend much extra to get fancy shocks, I'd tend to go with "normal" ones instead (of course then there's this extra button on the dash that's just begging to be put to work doing SOMETHING....)

[Pacific JDM Parts]

One other thing to check is the rear sway bar links and mounting bushes.Grab the bar and try to move it up and down and do the same with the links.Any movement will cause clunking/knocking over bumps.

[djelica]

Hey thanks guys,

I will replace the shocks with normal ones. Need to figure what is best option in terms of performance/price.

Oh and I did check the sway bar when I was under. Bushings have been replaced and it is solid. Looking more and more like a shock thing.

cheers, Darren