XJ Transmission Oil Coolers

[carvesdodo]

Very purdy Rodge ...

Does tigger get jealous and let the XJs tyres down when the XJ is getting too much attention & fancy bits


Havent made any changes to mine since Feb .....

With 50*c - 80*c being the FSM operating range ... Im happy at this stage with a fairly stable 66*c under normal town & highway driving conditions ... altho a fan would be handy to keep it below the 80* - 90* oil temps with high ambients and working the gearbox with a load.

Still .. 80*-90* is a damn sight better than the 120*s I was getting with the factory setup or just the two factory coolers I had mounted in series with just normal driving.

Will mess around with it after winter if need be .. probably relocate it to in front of the aux fan side and closer to the radiator and finally give the fan over-ride switch something to do.

Coolant temps are still a coupla degrees higher at a stable 93*-94* because of the oil cooler size/location.

[Rodgebone]

Does tigger get jealous and let the XJs tyres down when the XJ is getting too much attention & fancy bits

naw, only my wife gets jealous while her TJ sits gutted but Tigs knows whats in store for him... which reminds me i need to order a tranny cooler for the LS auto. been looking at Derale deep sump pans to go with another B&M cooler but cant really buy anything till i know which tranny im going to end up with. id like to find a 4L80E but will probably settle for a 4L65E or 60E as they are pretty common. i do know it will be a stacked plate unit mounted in front of a Novak alloy rad with another ProForm fan pulling both (same config as the last V8 project). hoping to have the V8 next week when i get time to go look.

[Hamsteh]

It's not a simple thread topic is it!?

I've been considering going on a trip across the Simpson with a few mates and figured even if I dont end up going this year, I should start getting the jeep in a position that it might just be survivable.

Once the cooling system is sorted (it actually seems to operate reasonably well at the moment) I figure the next stage is the Auto.

Now I realise everyone is aiming for the best possible performance from their cooling system, but I guess my question is that if i was to simply replacing the stock transmission cooler with something a bit more substantial (like a Flex-a-Lite from summit racing), and bypassing the heat exchanger. Could I be confident enough that the auto isnt going to cook on me? Or is it really a matter of having to go the whole hog to even attempt something like the Simpson?

Cheers folks, keep up the great work!

[kyphonii]

Originally Posted by Hamsteh

It's not a simple thread topic is it!?

I've been considering going on a trip across the Simpson with a few mates and figured even if I dont end up going this year, I should start getting the jeep in a position that it might just be survivable.

Once the cooling system is sorted (it actually seems to operate reasonably well at the moment) I figure the next stage is the Auto.

Now I realise everyone is aiming for the best possible performance from their cooling system, but I guess my question is that if i was to simply replacing the stock transmission cooler with something a bit more substantial (like a Flex-a-Lite from summit racing), and bypassing the heat exchanger. Could I be confident enough that the auto isnt going to cook on me? Or is it really a matter of having to go the whole hog to even attempt something like the Simpson?

Cheers folks, keep up the great work!

What I have learnt.
Do not run through the radiator.
Fit a temp sender in the pan. 1/8 Bspt or metric equivalent. Must know what temp the oil is going in to the transmission.
Transmission oil cooler the size of the opening in front of the radiator I think its 10" high and half the width of the radiator.
Replace the axillary fan with a10" or 11" ? spal at more than twice the flow.
Make shaw the engine driven fan is working, mine is the only thing you hear when at operating temp and highish rev. a bit annoying but it's flowing some air. removing the mechanical fan is an option BUT if you can't get more than 90 amp alternator then I would not be tackling the Simpson.

The 11" spal Extreme will draw up to 25+ amp. were are the amps coming from and thats only a 11".
I will stay with a mechanical so as to take load of the alternator.
It amazes me how people think they can get air flow through a crowded radiator at no cost.
Your max air flow has to be at 0 KPH, you can not rely on road speed to get your air.
I have not work out if a pusher fan to help the puller spal can be fitted in front of the cooler but that would get some air moving through the drivers side of the radiator.
Air flow costs HP either through a pulley driven alternator or a pulley driven fan.

[Hamsteh]

Originally Posted by kyphonii

What I have learnt.
Do not run through the radiator.
Fit a temp sender in the pan. 1/8 Bspt or metric equivalent. Must know what temp the oil is going in to the transmission.
Transmission oil cooler the size of the opening in front of the radiator I think its 10" high and half the width of the radiator.
Replace the axillary fan with a10" or 11" ? spal at more than twice the flow.
Make shaw the engine driven fan is working, mine is the only thing you hear when at operating temp and highish rev. a bit annoying but it's flowing some air. removing the mechanical fan is an option BUT if you can't get more than 90 amp alternator then I would not be tackling the Simpson.

The 11" spal Extreme will draw up to 25+ amp. were are the amps coming from and thats only a 11".
I will stay with a mechanical so as to take load of the alternator.
It amazes me how people think they can get air flow through a crowded radiator at no cost.
Your max air flow has to be at 0 KPH, you can not rely on road speed to get your air.
I have not work out if a pusher fan to help the puller spal can be fitted in front of the cooler but that would get some air moving through the drivers side of the radiator.
Air flow costs HP either through a pulley driven alternator or a pulley driven fan.

Cheers for the informative reply mate. I've read through this thread a number of times but since there's not yet a definite conclusion its all a bit confusing!

Engine temps seem reasonable, and clutch fan seems to be operating properly.

I've only very rarely noticed transmission feeling hot through the floor but without some numbers to attach to that 'feeling' that's not a particularly useful measurement I guess haha.

Definitely need to look into a sensor/gauge combo so I can get some ballpark figures I guess. It's all just time and money isn't it!

[Rodgebone]

i agree with kyphonii but i will say all this non sense about overloading the alternator by running added accessories will hurt fuel economy is crap...does anyone really think overloading an alternator is going to have a significant effect on fuel economy? what are we talking here: $15 bucks a year? who cares! if you are that nit picky about fuel economy then you should never have bought a Jeep (or any 4WD) in the first place! i have heaps of stuff on mine and my alt still keeps up (stock unit - original @ 230KM and never replaced or an issue). too much emphasis is placed on overloading the alt (as far as cooling goes) - too many high power accessories is another story but cooling fans dont cost much power-wise. the payback is much greater even if it does work the alt harder - i reckon 10x more benefit (for an XJ). as an example, i have a massive stereo system (2 hd amps), CB, driving lights, spotties, an auxiliary aftermarket cooling fan, a main fan (in place of the stock clutch unit for the engine) and 3 spals helping with the tranny cooler. no probs yet and these mods have been in the car for quite some time (enough to prove it wont hurt you). add away!

[grit]

fact is that at normal highway speeds airflow alone is keeping it all cool. Sand driving will increase engine load, inturn activating clutch or electric fans. The additional load to the alternator (from thermo fans) will not extract even half of the horsepower of a clutch fan. Making the strongest argument 'reliability'. I have a Taurus 2 speed thermatic in the shed along with a new copper radiator, I figure a servicable radiator would prove itself a safe choice in the most remote areas. I like the idea of locating a trans cooler between the radiator and AC fan.