How to test an Automatic Gearbox

Post by **side-show-bob** » 21 May 2007, 15:32

Hi all this is my first post on the web site...

I have been given a 1985 carravelle and was told that it had the auto gearbox overhauled three years ago. It started to leak a number of moths later and then so the story gose lost all its fluid and melted the internat plates (acording to the garage where it was taken) The guy i got it off gave it to his brother who drove it for several months before it died at traffic lights (apparantly due to the gearbox). it was then parked up for a year. I have found upon inspection that the fuel pump is dead which would explane it dieing at the traffic lights. My question is though i have had the engine running and have driven it up and down the drive (approx 10mtrs) and the gearbox gose into drive and reverse fine and travels fine, Can i check if the gearbox is ok without running it as it has no MOT or TAX? there is a leak which i belive to be coming from the gearbox sump and also a leak on the final drive sump, both of which will have new gaskets fitted.
Is there anything else i should check on the gearbox or final drive as i want to convert the van into a camper and need to know that the gearbox is sound as i cant aford to fix that and conver it.

Sorry for the long story.

Cheers
Rob

Post by **camper** » 21 May 2007, 16:25

A few ideas based on my own experiance upon owning a 2lltr Aircooled automatic T25 devon.Iternat plates could be the friction bearing parts that act as a kind of clutch.The ATF fluid colour is a good indication of problems it should not be dark brown but the same colour as replenished ATF fluid dextron which is red.The brown colour would indicate burning of the plates as to cause gear slipping when attempting to engaging D1 or D2 and changing gears bottom to top .You could try stopping the front wheels from moving forward some obstruction like a kerb.See if when selecting gear see if it will drive forward and up.Jacking up the back wheels might tell you if it will change from 1st 2nd & 3rd but it wont tell you if it slipping.If you change the sump gasket there is a gauze filter inside the auto box i would expect you may find metal fragments or small parts if there is.This may tell you the box is goosed

Post by **side-show-bob** » 21 May 2007, 16:30

Cheers for the advice i will try it the ATF is still bright red so i think there isnt any burning. My personal view is that when it emptyied the first time it was a poorly fitted seal and the garage saw an opertunity to make a quick buck. I dont think there is much wrong but as i said i havent driven it, so i will try and jack the reasr up and get it to change gear.

Post by **camper** » 21 May 2007, 16:51

Regarding jacking up the rear take prioity for safety using good axle stands dont forget you have a engine running and wheels moving.And it will not tell you anythink about the autobox holding gears or changing in diffrent road conditions ie hills and other.If you are a novice may i suggest you dont do this.

Post by **oorwullie** » 21 May 2007, 21:18

my suggestion would be to go get a friendly local garage man with his trade plates and pay him his hourly rate for a test drive and possibly pre- mot check. i'm assuming you're not on good enough terms with anyone to just be able to borrow the plates.

Post by **Rozzo** » 21 May 2007, 21:20

the first idea was the best one. chock the front wheels with bricks, then engage drive and see if it will drive over them. then try the same thing in reverse. if it drives over them easily there's probs not a lot wrong with it, then the only way to test the individual "gears" is to drive it uphill and down dale to see if it changes correctly etc.
dont have the wheels and transmission spinning at 60mph on a jack as it could all end in tears.