Transmission Fluid In Coolant

[jason125]

i have transmission fluid in my coolant and my transmission has started misbehaving. i have been told that i need to change my radiator and replace my transmission fluid . i have found a radiator on eBay for £99 but have never replaced transmission fluid . has anyone had experience with such a task or has anyone had the same problem as i have had . do you know of a more affordable alternative to t - IV transmission fluid ?

[sir john]

Dont know the answer to your question buddy but i have heard of this problem on many Mercs. If i were you id be looking on their forum for a bit of background.

[John N]

i have transmission fluid in my coolant and my transmission has started misbehaving. i have been told that i need to change my radiator and replace my transmission fluid . i have found a radiator on ebay for £99 but have never replaced transmission fluid . has anyone had experience with such a task or has anyone had the same problem as i have had . do you know of a more affordable alternative to t - IV transmission fluid ?

Jason

Stop driving the car until you get it fixed, water in the transmission fluid will wreck the gearbox and that may cost more to replace than the car is worth!

I have heard of this problem before with the LS430, I was talking to one of the technicians at Lexus Manchester when I was fitting a transmission cooler my 430, he had encountered the the same problem, and it had wrecked the cars gearbox.

The transmission cooling pipe from the gearbox goes through the bottom of the radiator to transfer heat from the gearbox to the water in the radiator. There will be a leak in the pipe inside the radiator allowing water to get into the transmission fluid and transmission fluid to get into the coolant water.

The alternative to replacing the engine radiator is to fit a separate transmission cooler radiator in place of the pipe through the radiator. You then block the ends of the leaking pipe to keep the water in the radiator.

You need to get to a good 'auto transmission' workshop to have the transmission fluid changed asap, I don't think it is a DIY job as you can't get all the fluid out of the transmission by taking the drain plug out. A portion of the fluid remains in the torque converter, this will also be contaminated with water and will need changing.

This is the transmission cooler I fitted to my car: http://www.kenlowe.com/oil-coolers/automatic/index.html

Do not skimp on the quality of the transmission fluid you use, but a good workshop should be able to supply it cheaper than Lexus.

John N

[steve2006]

That seems to be a backward step. My 1994 import LS400 has a seperate transmission cooler fitted as standard below the radiator and behind the bumper and the later model has an integrated radiator/transmission cooler?

[jason125]

i have transmission fluid in my coolant and my transmission has started misbehaving. i have been told that i need to change my radiator and replace my transmission fluid . i have found a radiator on ebay for £99 but have never replaced transmission fluid . has anyone had experience with such a task or has anyone had the same problem as i have had . do you know of a more affordable alternative to t - IV transmission fluid ?

Jason

Stop driving the car until you get it fixed, water in the transmission fluid will wreck the gearbox and that may cost more to replace than the car is worth!

I have heard of this problem before with the LS430, I was talking to one of the technicians at Lexus Manchester when I was fitting a transmission cooler my 430, he had encountered the the same problem, and it had wrecked the cars gearbox.

The transmission cooling pipe from the gearbox goes through the bottom of the radiator to transfer heat from the gearbox to the water in the radiator. There will be a leak in the pipe inside the radiator allowing water to get into the transmission fluid and transmission fluid to get into the coolant water.

The alternative to replacing the engine radiator is to fit a separate transmission cooler radiator in place of the pipe through the radiator. You then block the ends of the leaking pipe to keep the water in the radiator.

You need to get to a good 'auto transmission' workshop to have the transmission fluid changed asap, I don't think it is a DIY job as you can't get all the fluid out of the transmission by taking the drain plug out. A portion of the fluid remains in the torque converter, this will also be contaminated with water and will need changing.

This is the transmission cooler I fitted to my car: http://www.kenlowe.com/oil-coolers/automatic/index.html

Do not skimp on the quality of the transmission fluid you use, but a good workshop should be able to supply it cheaper than Lexus.

John N

[ambermarine]

i have transmission fluid in my coolant and my transmission has started misbehaving. i have been told that i need to change my radiator and replace my transmission fluid . i have found a radiator on ebay for £99 but have never replaced transmission fluid . has anyone had experience with such a task or has anyone had the same problem as i have had . do you know of a more affordable alternative to t - IV transmission fluid ?

Having read this sorry tale It is a new phenonemum as far as the forums go and sounds horrendus

Personally I would not bother getting this box taken out to service at a Auto transmission shop

It is probably better to put another box in. Apart from the present situation as your box stands these boxes are usually bombproof.

They are available on eBay and there are Mechs who can fit them without going to Lexus.

But depending on how much money you want to spend and bearing in mind how much your car is worth it might be less stressful to say goodbye and invest the money in a another Ls.

[alan.skinner1]

I have the same problem atf in coolant and vice versa, the gearbox still worked of sorts when this happened, so hopefully can recover gearbox.

I have replaced radiator and now need to get fluid/water mix out of transmission the mix is pink in colour and very oily still.

Can this be done with disconnected cooler return pipe into a container by running the engine long enough to pump out approximately 1.5-2 litres of fluid at a time and replace with same until I get a clear response.

Would appreciate any help on this?

Alan

[Tulpen]

If you go onto the US Lexus forum, there are instructions for changing 430 transmission fluid.

[ambermarine]

When I changed the fluid on my Mark 1 the method was basically put two litres in and take two out until the fluid is pink and clear.

I have a special 12 volt oil extraction pump for which I once had the distribution rights in Europe .

It was designed for extracting oil from small marine engines via the dipstick, it is no longer made but there are vacuum pumps that do the same job available at chandlers.

The fluid is extracted via the dipstick tube and I think I used 15 litres in all .But a good guideline is twice as much as the capacity of the box.

Method;Extract two litres ,replace with new ,run round the block repeat the excercise until the fluid is clear,

draining from the sump will remove a couple of pints as most of the fluid is held in the torque converter and the box.

[MNP]

Sorry to be the harbinger of doom and gloom but my experience with my Land Cruiser is that you

can fix the problem and flush...and flush...and flush and maybe extend the box life by a year or two

with occasional breakdowns. In the end the box will more than probably need a re-build.

Good luck...Mark.

[steve2006]

Another thing to consider with a secondhand transmission is to ensure that the car being broken was not due to the intercooler problem in the 1st place, hopefully most scrapyards would be honest and not sell a transmission likely to be already damaged but the hassle of fitting another faulty box would be quite upsetting.

Accident damaged breakers will probably be the best bet,also ensure you get the matching torque convertor from the breaker do not reuse the original one.

[mikeyv]

When I changed the fluid on my Mark 1 the method was basically put two litres in and take two out until the fluid is pink and clear.

I have a special 12 volt oil extraction pump for which I once had the distribution rights in Europe .

It was designed for extracting oil from small marine engines via the dipstick, it is no longer made but there are vacuum pumps that do the same job available at chandlers.

The fluid is extracted via the dipstick tube and I think I used 15 litres in all .But a good guideline is twice as much as the capacity of the box.

Method;Extract two litres ,replace with new ,run round the block repeat the excercise until the fluid is clear,

draining from the sump will remove a couple of pints as most of the fluid is held in the torque converter and the box.

I've got a pump like that, Conrad UK sell them, and some on eBay too.

Here's a link to the one on Conrad.

http://www.conrad-electronic.co.uk/ce/en/product/854215/Mannesmann-Oil-Suction-Scavenge-Pump-3lmin12V?ref=list

I did an oil change on a Toyota Hi Ace 2.2 diesel, and found it a bit fiddly to be honest, in fact I had to remove the dipstick tube so the plastic tubing from the pump could be inserted in to the sump.

Also, me being me, I had to remove the sump plug to be sure the oil had actually all drained out, and, to be fair, it was bone dry, but kind of defeated the object a bit.