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swanny
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my 78 3.5 auto. she takes ages to change up gear unless you give it some welly. is this normal as i have not driven a automatic before. if not any ideas ??.

thanks swanny :unsure:

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78? So it's probably a Schuler conversion? With Chrysler Torqflite 727 speed autobox and Ferguson Formula transfer box?

They tend to change out of 1st fairly rpaidly, and with a bit of a clunk too. The 727 is pretty robust, but it is sensitive to incorrect adjustment of brake bands and kick down linkage.

Give it a fuild and filter change, set the brake bands and the kick down linkage up correctly, and see what it's like. The Haynes book of half truths covers all this fairly well. One word to the wise, the torque figuires given for the brake bands are in lb F in, not the usual lb F ft. So make sure you have either a lb F in torque wrench or the correct conversion factors handy. The brake band adjuster is 1/4" square.

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You might want to check your post, you have said the torque figures for band adjustment 'are in lbf ft not the usual lbf in'. I think you meant to put it the other way round! :unsure:

But, as said, be VERY careful that you get this right - it is lbf in. If you use a torque wrench that is calibrated in lbf ft and set it to 72lbf ft you WILL damage things. Catches a lot of people out.

To give you an idea, 72lbf in converts to approx 6lbf ft so you can imagine what will happen if you get it wrong :o

Unfortunately the Haynes does not give the speeds that the box should change at under normal acceleration which I think you need to check first in view of you saying that you have never driven an automatic before. Hopefully someone on here will come up with that?

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78? So it's probably a Schuler conversion? With Chrysler Torqflite 727 speed autobox and Ferguson Formula transfer box?

They tend to change out of 1st fairly rpaidly, and with a bit of a clunk too. The 727 is pretty robust, but it is sensitive to incorrect adjustment of brake bands and kick down linkage.

Give it a fuild and filter change, set the brake bands and the kick down linkage up correctly, and see what it's like. The Haynes book of half truths covers all this fairly well. One word to the wise, the torque figuires given for the brake bands are in lb F in, not the usual lb F ft. So make sure you have either a lb F in torque wrench or the correct conversion factors handy. The brake band adjuster is 1/4" square.

The brake band adjusters are usually pretty rusty - doesn't this affect the torque readings?

And then you say 'fluid change' do you mean the pathetic proportion that comes out when you undo the drain plug, or getting the whole lot out by flushing it?

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Well spotted, I've changed it now.

And another word to the wise, it's not as simple as 1 lb F ft = 12 lb F in either. Don't ask me how I learned that :blink:

I bought a good lb/in torque wrench, they're not that easy to find, cost me about £80, glurk, and adjusting brake bands not very often is all I intend to use it for, but I figured buying a cheapo was pointless given this is a crucial job, however there may be good ones available for less??

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Right, in no particular order.

I've never found the brake band adjusters to be rusty, maybe I was just lucky? As long as the threaded cetnre part is free to turn, I wouldn't have thought it would affect the torque values. One of them is inside the box, so it most certainly shouldn't be rusty.

There's no easy way of flushing it ALL out, I tend to drop the drain plug after a run so it's well warmed up, then pop a hose off the oil cooler and let compressed air blow as much ATF out as I can get out. There is allegedly a TC drian but it's a right faff to get at, it's meant for when the TC and box are off the vehicle. Once you've got the sump off to change the filter, more ATF usually dribbles out.

I've never found a cheap lb F in torque wrench, I did pick one up cheap at a local military disposals place, but it wouldn't have been cheap when new, also got a torque wrench calibration doo hicky form the same place.

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