Sound's like a daft question to me but yes really... would you install an oil cooler on an auto box in a Z32 N/A????.

I ask this because I sent mine to a 300ZX specialist (apparently) to have a new radiatior fitted and after 6 months my auto box has packed up and today I realised he bypassed my trans cooler when he fitted the new rad.

This is the short story... the long story is is in the next posting for those interested. (I realise that somke like the short threads and some like the full technical story).

He stuck a manual rad in and didn't bother putting anything in to cool the gearbox oil? Doesn't sound like a good idea to me! :nono:

 

On the other hand, people seem to think that the small gearbox oil cooler in the autobox rad doesn't do much, so maybe it would have failed anyway. That's presumably what he'll claim. :(

If I had an auto? Yes. Heck, if my J-spec was an auto I'd have upgraded the cooling on the box within a month of getting it. They burn up. Your autobox isn't cooled properly, especially if it's a J-spec import? Well it's gonna burn and that's that. Search this forum: that answer is everywhere. Sorry to say, but whilst I'm no expert, not cooling your autobox is a dumb idea, and your bloody mechanic should have known that. I barely knew which end the right end of a wrench was which when I first looked into getting one of these cars a couple of years ago, so almost anyone else is without excuse.

Deffinatly, with no cooler at all it will fry in no time. Not driven mine since fitting an external one, but beforehand the box got hot enough that you could feel the heat through the tunnel!

That might be pretty normal: I have a manual and the tunnel gets warm after an extended period of driving.

well I was gonna post the full storey but quite simply a so called 300zx expert that posts on here installed a new rad in my car and chose to put a peice of hose in to simply connect the trans cooler pipes together.

6 months later my trans cooked (yes I am suprised it lasted that long too).

I called him this evening to ask what planet he was on when he did the job and he told me that it was quite normal practice with a N/A as the tranny cooler was usless anyway on an import and everyone gets rid of em (do you think he missed the point here or what???).

Gimme your thoughts people... I know what I think.

By the way... I am a mechanic and I know that but I trusted this guy cos he post's on here as a 300zx specialist (sorry I cant say who it is at the mo cos this is in the hands of my solicitor at the moment)

Why your mechanic would say such things beats me. What I have heard plenty of is dead autos! I blew mine up within a few months of ownership. The standard tranny cooler (built into rad) is small & easily clogs. I strongly suggest anyone with a auto fit a larger, external cooler to prolong it's life.

 

Here's a pic of my oil cooler.

What they say above, yes these cars need a cooler for the auto box. Mines an import and it was one of the first things I did this year after reading about it here and whilst I agree that the original cooler is next to useless, removing it completely does not make sense unless it is to fit a larger one. It's is a known issue and I think this should have been explained to you.

 

After fitting my cooler I took it for a spin to check everything out and it was a cold day in April, only went about 5 miles and I couldn't believe how hot the new cooler got, so I am not suprised these things fail with the existing J spec cooler let alone none whatsoever.

 

Gaz

I have a NA auto.

 

I've had it getting on for three years.

 

I'm the first UK owner.

 

I haven't fitted an extra oil cooler.

 

The car's been fine.

 

Maybe the TTs need them more than NAs?

 

In the 300ZX Enthusuast's Companion book it says the extra oil cooler was fitted to european spec cars allow for sustained high speed driving and I think it means autobahns.

 

I'm a big fan of not fixing things that ain't broke. If you get someone to mucka bout in there it may cause more problems than it solves.

 

Then again maybe my autobox will explode tomorrow. Who knows?

 

I think 'you have to fit one' is an easy-to-repeat piece of information people will tell you even if they have no first hand experience themselves.

 

In short - cost of getting a decent oil cooler and getting a decent mechanic to fit it would be £200 odd I'd guess.

 

If your autobox goes pop you can probably get a manual conversion for about £1000 all in if you do a little legwork yourself.

 

Maybe the problem is that many autoboxes are about 15 years old now and would have gone pop anyway?

Due to the way an auto box works, it WILL heat the oil. You therefore have to cool it or it will get hotter and hotter and eventually break down. No matter how bad the stock cooler is, its still better than nothing and is obviously doing its job considering the box lasted up to now ;) The problem with the standard system is that it uses the engine coolant. This is already at ~80 deg C so you will never cool the oil lower than that. An external cooler however uses ambient air so gives you an extra 60 deg advantage. On the downside, liquid-air coolers are no where near as efficient as liquid-liquid coolers so the difference isn't as much as it first seems ;)

has anyone got a picture of the gearbox cooler from a j spec and uk spec. mine has a separate oil cooler fitted to my j spec so it must have been done at some point. im not sure if it is just a uk one they have used

Due to the way an auto box works, it WILL heat the oil. You therefore have to cool it or it will get hotter and hotter and eventually break down. No matter how bad the stock cooler is, its still better than nothing and is obviously doing its job considering the box lasted up to now ;) The problem with the standard system is that it uses the engine coolant. This is already at ~80 deg C so you will never cool the oil lower than that. An external cooler however uses ambient air so gives you an extra 60 deg advantage. On the downside, liquid-air coolers are no where near as efficient as liquid-liquid coolers so the difference isn't as much as it first seems ;)

Too True!! Its alot cheaper to fit an oil cooler than to repair or renew the Transmission ;)

Ive got a jap TT and I fitted a Koyo and added a new oil cooler for the autobox, plus the engine oil has its own cooler anyway. The autobox cooler is fitted to the koyo and sits right in front of the main fan so it always has good forced airflow across the fins all the time.

 

I decided after reading some of the threads that I'd get the car properly cooled its simply a good thing to do rather than do the auto box for a few grand!!

 

Its shocking how much heat the Koyo and oil cooler throw out, I cant imagine letting the whole car fry itself for the sake of a few quid.

How many people have had an NA and had the auto box go?

I,ve fitted a nice big 10 row Mocal one on mine :hyper: :hyper:

I wan,t prepared to take the chance after reading up on here :bow: :bow:

Also got the same for the engine oil :nana2:

right

autobox is just a big hydraulic pump to put it simply...if it isnt cooled at all the hydraulic fluid will totally fry and the heat degenerative components in the box will break, doesnt matter wether it is a na or a tt, the main difference will be on acceleration where the tt one will be put under higher pressure than the na, at all other times the box's will be under the same conditions.

Hydraulic oils have a maximum operating competancy at given temperatures ,As the temperature of petroleum-based hydraulic fluid increases, its viscosity decreases. If fluid temperature increases to the point where viscosity falls below the level required to maintain a lubricating film between the internal parts of the component, damage will result.

 

The temperature at which this occurs depends on the viscosity grade of the fluid in the system. Hydraulic fluid temperatures above 180°F (82°C) damage seals and reduce the service life of the fluid. But depending on the grade of fluid, viscosity can fall to critical levels well below this temperature.

 

if you need any more info i will go look out my tech books from my hydraulics course and see what i can dig up for you

hmm well in a stock 300 the ATF will certainly be upwards of 82C, as said, the coolant is about 80c in the rad so thats the minimum temperature it will enter the box at, and it will only get hotter during its time inside the box.

so where is my pictures of a standard autobox cooler?

Seems to me gentleman ( and ladies), that this is a simple case of prevention being better than cure, No?

Oop's I meant gentleMEN. A bit squiffy don't ya know, hic!

better safe than sorry bud ....and my auto box run's cooler now...

 

..

OK guy's. Here's a new one. Where's the best place to get an oil cooler? Go!

OK guy's. Here's a new one. Where's the best place to get an oil cooler? Go!

luke@ z centre

 

do a search online, top bloke has the gift to sell you more than you phoned up for, and also your phone bill doubles from the length of time on the phone to him :rofl:

I took my radiator cooler out of the loop and fitted a mocal cooler instead in front of the oil cooler. I'd recommend doing it. I've since fitted a manual radiator to it as my old one was getting a bit long in the tooth!

exactly as dave marley said at the beginning of this text. the so called speciallist put a manual rad in and bypassed thye cooler (just looped the pipes back to the box).

AND when contacted he did say that the original coolers are not much cop anyway and the box probably failed for other reasons.

He does this type of fix all the time apparently... WOULD YOU TRUST HIM TO WORK ON YOUR CAR???