auto issues

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B-Hive
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auto issues

Post by B-Hive »

The Mk1 auto is getting a good workout lately, and the GT is progressing nicely..however the auto is showing signs of aging or need for a service.. opinions appreciated.

The problem is that when the transmission is warm/hot, it has this trouble changing back out of 4th when decelerating to a quick stop. It will grumble/rumble loudly as it tries to drop back. Give it a few extra seconds and it will always find the lower gears (usually 1st by this stage). If I keep it in 3rd (where the torque converter is partially bypassed) I get the same issue but only partially.

So long question short. Does the trans need a service or is it potentially more terminal?. I replaced the fluid about 5k mile ago, but did not clean the filters as it was a job that required removing more bits than i was prepared to. Car is 85 and has 105k miles. For the most part the transmission is really lovely and changes very smoothly, engages without jolt etc..

so yeah ..any input please ..

Thanks
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86 BX TRS Mk1
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Tim Leech
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Post by Tim Leech »

I would check the fluid level first to be sure, even though you have changed it recently.
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citroen7
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Post by citroen7 »

what colour is the oil? if it is murky and not a nice red change it ,if possible use a suction device to empty the box completely my car was a lot better after an oil change also check the BOL there is a particular proceedure to follow when checking the level.
B-Hive
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level ok i think

Post by B-Hive »

Roverman wrote:I would check the fluid level first to be sure, even though you have changed it recently.
hello again fellow rare MK1 GT owner. In terms of the fliud level, I thought of this a little while back, tested the level and it was a little high, so drained it back to specified level..having said that I'm not 100% sure it's right but reckon its close enuf not to matter. The transmission also does this after the car has been idle for a few months..but hot daily usage now has it cranky changing down. its otherwise a lovely transmission, that you can feel it changing down as u decelerate (unlike jap transmissions that kinda go limp and just coast as u decelerate).

I'm thinking it is filters that the longer there is positive fluid flow, the greater the the chance of build up against and on the filters.

so i guess its time for another service interval,, whilst she is laid up I will hopefully resolve front end knocking issues... (sub frame, drop links)

we'll see
Current
85 BX GT Mk1..
86 BX TRS Mk1
87 BX TRi


Gone
85 BX TRS mk1 auto... SOLD
90 BX TRi..parts....cubed
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Way2go
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Post by Way2go »

Just a thought.............When you changed the fluid, you did use Dexron 2 and not Dexron 3 didn't you? Dexron 3 is wrong formula for BX ,will be problematic and lead to damage to the transmission as has been documented in this site before.

If you have used this in error, then you need to totally drain the system, including the torque converter and refill with Dexron 2, and its improved lubrication may free free up what has started to bind.

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docchevron
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Post by docchevron »

IF you've used DIII and the bix is hanging in top then it's too late.

If you have not used DIII then I'd seriousley change the filter and and check for signs of metal filings in it and around the filter basket.

Might be worth checking the kickdown cable is still operating aswell.
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B-Hive
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she has the good oil

Post by B-Hive »

Thanks everyone so far..

I was careful to use the correct oil being the D2..yes I've heard horror stories about using the D3

Kickdown all adjusted..
Current
85 BX GT Mk1..
86 BX TRS Mk1
87 BX TRi


Gone
85 BX TRS mk1 auto... SOLD
90 BX TRi..parts....cubed
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Tim Leech
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Post by Tim Leech »

Good luck!
Lots of Motors, mostly semi broken....
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