Wallsy, you sure throw up curly questions! The pressure test results would be good to know. They should at least measure the flow rate at 2 points:
1) straight out of the trans;
2) just before the return to the trans;

If the flow is good coming out, but it's bad going in then there's a blockage in the lines/TCs.
If the flow is bad coming out... start scrapping the cash together for a 'Brian's fix' (i.e. a JW trans air freighted from the US)!

Hopefully it is just a blockage in the lines/coolers and it can be resolved. 3rd guy seems on the money there! He actually wants to work out the cause before trying to rectify it.

 

G'day Wallsey,

Well the plot thickens.

I though it would be something very strange for someone to remove the 7.3Ltr OEM and just put that 350X350 Tube Fin in there.

Well now you know you have still got the 580mm X 140mm 7.3Ltr OEM in situ here is what I'd do.

Do the flow test yourself with current set up.
Check you have full fluid in tranny.
Get 2 x Clean buckets.
Simply disconnect the return line to the tranny at the tranny and attach/clamp a clear plastic hose to it and run it into one of the clean buckets.
Start the truck and as soon as you see a good good flow swap hose to second clean bucket and run it into there for 15 seconds, shut off engine.
Note: If no flow or very little at all, then your tranny is by-passing (more on that later).
Minimum flow is 32 ounces in 15 sec but should flow 32 ounces in 10 sec if all good.
32 US Fluid Ounces = 946ml (close enough to 1 ltr).

If flow is good then you don't have a flow rate problem but a cooling efficiency issue.
However if the flow rate is less that desirable then do the following:

Disconnect the lines from that Tube Fin cooler and take the Inlet line that was going into that Tube Fin cooler and connect it to the return line going back to the tranny (the line you already have the clear hose clamped to).
Have your now 2 x empty buckets ready.
Check fluid level is topped back up.
Repeat the test.

If you get the correct flow rate then that Tube & Fin cooler is your problem.
If the flow is still less than desirable then you do have a restriction/blockage somewhere in the system.

Your set up now has effectively 3 X Coolers.
No 1 is in bottom of radiator; No 2 is the OEM 7.3Ltr Stacked Plate & Fin cooler and No 3 is the Tube & Fin Cooler.

Note: As explained in an earlier post I have three also but the No 3 is a Stacked Plate & Fin cooler and I have no flow or heating issues.

As I've noted before those Tube & Fin coolers are not very efficient and restrict flow no matter what the sales talk is.

If you don't want to do all this above testing just disconect that Tube & Fin cooler and connect what was the inlet line to it to the return line back to the tranny.
This will have you back at stock. Check your fluid level and take it for a run and see if you get those high temps.
If you don't then that Tube Fin is your problem. It is either totally not fit for purpose, restricting flow or blocked.

The other thing with these trannys is that there is a by-pass fitted to maintain flow should a blockage occur in either the radiator bottom or in the OEM (or any other cooler fitted for that matter).
If there is a blockage then your fluid is not going through any of the coolers at all but by-passing to maintain flow.
This would possibly explain those very high temps when not even towing or no load .

Anyway which ever way you go to chase down this issue, it is solvable.
If it turns out to be a blockage then we need to look at its root cause.

Cheers,
Reg

 

Reg,
Something you didnot cover. What if it is the pump in the gearbox? That scenario scares me greatly. Do they go often? I am praying it is an easy and rather cost effective fix. I have enough to do to this truck on the month off I have at chrissy without gearbox issues as well. I would do the test Reg if I had the time and resources, but am flat out with work at present. I will just pay the $90 and let him stuff around under the truck intead of me. My time is coming over chrissy to get aquainted with the engine bay and under carrage.

Simon,
3rd guy is pretty good. As long as he doesnt try to scam me for a pump when that is not the issue, and it turns out to be blocked lines, which I am hoping for. I will let him know that I now know how to test it, and if the out come is not favorable, I will get a second opion or get the stuff and test it myself to double check. As a matter of interest, what is a JW trans worth, (worst case scenario)?

 

Hi Wallsy, hope for the best, prepare for the worst, that's all you can do. Brian is the JW trans guru - he said about $6k landed in Australia via AIR FREIGHT. While that sounds expensive, it is still cheaper than any re-man I've heard of done locally. Obviously fitting cost is on top of that. You could ask your 3rd guy for a trans fitting quote.

See what comes of your pressure test. Maybe get the guy to back-flush the coolers to remove any blockages in the lines/coolers, then hook it all up again and see how it goes. Who knows how long it will last if you nurse it. The thing isn't busted yet - apparently the will shifts start to get really slow as the internal pressures drop and the final tell-tale is that it looses reverse.

By that time you'll want to have a JW trans on route 'Brain style', and enough life left in the stock trans to pick up the JW from the freight terminal and get to the trans shop.

In the meantime what your trans temp gauge & back off big time if the temp goes > 212 (100c) - although Reg/Brian/Rod might know of a more appropriate 'normal upper range figure'.

Also, hang in there mate. I'm sure your luck will change with a little bit more persistance, F-trucks and flea-bay is not a combination that is likely to lead to a good outcome for you!

 

G'day Wallsey,

A pump going on the fritz is possible but unlikely to be causing the high temps, you would be having shift problems before that.

Where is your temp being taken?

Is it from the PCM via the OBD11, or is a guage via the sender in the port on the side of the tranny.

If its from the OBD11 then the temps are most likely to be close to true.
If its from a guage then the Guage may well be out of calibration ( on the fritz).
Have you tried another guage if this is the case to eliminate a possible dodgy guage?

I say this because 240*F is pretty well tranny wrecking temp. If not a tranny failure you would most probably have had the front seal on the tranny give way at those temps and spew ya fluid all over the deck.
That seal is one of the first things to go at high temps.

34 to 35" tyres on these trucks with a stock tranny and stock or near stock cooling will build temps quickly also.
What size rubber are you running?

It is obvious that the PO was having cooling issues, so what damage had been done before he put that extra cooler in the system.
He could have burnt the oil (a few times) and the heat caused excessive clutch wear and the debris has accummulated in the cooling system and has clogged it up. This fine debris packs down in the bottoms of bends in those Tube & Fin coolers and also packs in the corners and bends in the valve body galleries .

It's painful but it is a process of elimination of the variables that can cause high temps.
But 240*F is bloody hot mate and if it has been reached on a number of occassions, then you most likely would have suffered some sort of serious failure before now ???

Here's hoping you can sort it asap mate.

Cheers,
Reg.

 

Simon,
The first guy I saw said he did rebuilds;
1st was a stock rebuild for 6K
2nd was for a tow arrangement, billet converter for 8.5K
3rd was for a superduty build, billet coverter, shafts etc for 11.5K.

Pretty expensive hey!! I checked the sender unit on the gearbox last night and cleaned it, just in case it was giving faulty readings. Then I took it for a 20min run out to the bay. With no cars in front, cool air blowing and sitting on 100Kmh the temp struggled to get over 200F. Then I brought it back and went through a series of traffic new where I live. Bang, straight up to 240F. It just hates sitting and waiting at lights, with no cool air coming in.

 

Wallsy, it's done this pretty regular right? And like Reg says, at that temp they spew (burp) trans fluid out of the front seal. It really does sound to me like you might have a cooler blockage AND a miss-calibrated gauge. You could pull the gauge sender out of the trans, drop it in just boiled water and then check the temp on the gauge to see if it is close to 212.

I would not be spending $$$$$ on a locally built trans when you can get a JW landed in OZ AIR FREIGHT for the cost of a 'stock rebuild' !!!!!

Normal temp on these trans in traffic like you described would be 175F.

 

Reg,
I am running 35 inch Dick Cepek FC2 all terrains on 10 inch rims. The temp is being taken from a Banks trans temp gauge via a port in the side of the tranny. Note, and all the shops have asked me, I have not seen the warning light on the dash come on regarding the high temp. I have not tried another gauge. I just figured it was a banks so reasonably quality. It could very well giving dodgy readings.

The reason why, is when I purchased the F350 from emerald, I flew up and drove it home. It travelled in roughly 28* temps for pretty much 9hrs straight. The only thing that stopped it was dropping a seal on number 7 injector, and as a result ended up getting towed the remaining 90km home. It had already travelled close to 900km with no issue running at close to the 240F temp.

Got the box serviced a couple of months later due to a leak for the dip stick, that was always there, and no burn't oil.

I mentioned to Simon that I cleaned the sender connection for the guage at the box and took it for a run out to the bay, about 20mins. In the cool night air, it struggled to get to 200F. I then brought it back and took it through a series of traffic lights near home and Bag, straight up to 240F. it just hates sitting at lights etc.

So the truck has pretty much always run at this temp, with no breakages. Lately it seems to be shifting better than ever. I just assumed that it was normal as the 240F is at the end of the green on the guage, until Simon mentioned that his got nowhere near that hot, even when towing. Thank heavens for you guys and your vast knowledge of these vehicles. It helps heaps talking to you guys.

 

Simon,
I have never seen this trans spew oil at all. My previous vehicle as a nissan patrol with a worked injected motor out of a torana. It had a t700 auto in it out of a commodore. That had a stuffed gearbox. I knew this because it would take up to 5 secs to select reverse.

The truck jumps in reverse pretty much straight away, and then drive. So pressures should be ok, I assume.

So yes. It has done this pretty regularly. The more I think about it the more I think it is a blockage and crap front cooler, which as Reg says, is adding to the problem. The PO was a bit of a bush mechanic. I reckon he sold the truck because it had no preventative maintenance done, and was starting to get a build up of issues, ie leaking HPOP, Bellow up pipes, over heating.

 

G'day Wallsey,

It is starting to look more like a dodgy gauge reading mate.

Running 'true' temps like that would have long ago caused a tranny to pull a big 'harrrumph!!' and bale up on ya.
Just try that simple test as suggested by Simon. Stick the end of the sensor in the jug and when it boils see if it reads 100*C or 212*F. (presuming you are at or near sea level and not living at Mt Hotham lol)

Optimum running/efficiency temp for these boxes is 160*F to 180*F.
Be concerned at 200*F, stop and let it cool at 220*F.
It's toast at 240*F.
In fact IIRC the truck's management system will go into limp home mode if it sees 240*F (I'll check that out and get back to you).
If I'm right then your box has not seen those temps and you do have a dodgy guage.
As you say yourself you have had no warning signs.
Have you had a code reader or Scan Tool put on it to see if you have any Codes?

It's startin' to look like a cheaper fix than havin' to get another slush box.

Banks gear only cost 'more' and not necessarily 'more' better .

If like you say, the oil is good, it's shifting good then it is most likely is good. Don't throw hooch at another tranny yet, do the simple fault finding already suggested.
It may well just be a dodgy guage. May well have a build up of ****e in the coolers .. get em flushed out ... better still .. ditch that Tube & Fin and replace it with a Plate & Fin. You can get then from Davis Craig here in Aust.
If the tranny is good. Next fluid change drop the pan, fit the JWVB, put in a new filter and go with the Synthetic Castrol Transmax 'Z'.

Do another favor to ya truck and don't fit 35" Tyres next time you need new tyres mate. 33"to 34" max.
35s are not only chewin' juice, they are stressing the front end steering, and the ball joints. Also givin' the tranny heartache.

Cheers,
Reg

 

Wallsy, his loss is your gain. As you say, the trans is holding up, I reckon it is a simple blockage and a high reading gauge. Is the temp gauge mechanical or electric? Mechanical will have a tube usually covered by a coiled wire protective sleeve running from the sender unit to the gauge. I've seen on the US site that mechanical gauges are really popular over there (and you've got a US import). No joke, if it is a mechanical gauge it may be just a question of opening up the gauge, putting the sender in just boiled water, then bending the needle to point at 212! Call it the 'bush recalibration'.

If it is an electric gauge, you could try replacing the sender unit. I'm using 'Race Tech' gauges that I bought off Ebay - electric stepper motor gauges made in Taiwan. $50 will buy a new oil temp gauge & sender. So far I've found them to be pretty accurate in that the values reported on them - I have 6 - all tie in with what I've expected and expereinced. The fuel pressure one has really been spot on. The oil temp showed the trans temp went to 175 then held that temp - exactly like they were saying on the US forum.

There are a few brands that I've noticed DON"T seem to be held in high regard on the US bros site including Air-Raid, K&N, and Banks funnily enough... Would love for you to do the boiled water test and let us know what you think of Banks afterwards!

I reckon that your shop 3 should be able to back flush your TC's and solve your trans temp problem for about $200!

I was posting this as Reg also replied. We concur!

 

Reg,
I have had the scan done on the truck a few months ago when the ICP went. No codes wereregistered for anything at that stage. I will get the pressure test done and see what the result is. I will also do the test on the sender that simon suggested just to see the accuracy.

I am running 35,s as I have just had the complete front end done up. Even the intermediate shaft repaired to take the play out of the steering. It actually drive slive a car now. 35,s seem to be ok but I wouldn't go any bigger. Alot of the other guys in our area that have them are running 37,s and 38,s. I notice a little bit of a drop in fuel ecomony, but that is fine with me. I also put a twin steering damper set up on it to assit with the larger tyres. Also twin tower shocks as you have. The dampers make a huge difference, as one pushes and the other pulls all the time.

So pressue test, then sender test. Then I might have an idea of where to go next.The plan is to get a much larger and heaps better quality cooler on the front just behind the grill and assisted with a thermo fan.

Also in the new year, after the HPOP job is done and bellow up pipes over chrissy, I will be looking at a large trans pan and JWVB form Clay. Will also change the fluid out then. The truck will have hopefull done 2000k by then, maybe. It is not getting used much at the moment. Once a week to pick up the kids from kindy. That's it.

 

Simon,
Its a banks Dyna fact, electric gauge, with just an electrical wire to it. Simple as appently. I will test the guage and let you know. Maybe no more banks gauges for me then. Time will tell. I am dropping the truck off tomorrow and heading up to gladstone for the remainder of the working week, picking up the truck again on friday arvo. I will let you know the out come of the pressure test then. Finger crossed it,s all good.

 

G'day Wallsey,

Well it looks as though you've got a good plan to run with and hopefully you will have your issues with the tranny sorted .

As Simon says, it will more likely be the sender unit on the TFT temp than the actual guage seeing it isn't a mechanical guage.
I got the ISSPRO Performax Guages from Clay some time ago and fitted the truck up with them. Easy to fit and I have a Pillar mount with EGT, Boost and TFT. Then inset into dash I have Fuel Press, EOT and ECT guages.

Good idea to get a better "good quality Stacked Plate & Fin Cooler with thermo fan. That's similar to what I did but I just done my own.
JWVB, new filter & Synthetic Fluid will see you good .

Each to their own when it comes to tyre size. Coming from an engineering background I'm just not a fan of going too big on diameter above original design.
I say that because the gearing and total drivetrain is designed around a narrow band of efficiency. With our 3.73 Diff ratio 35" is in my opinion the upper limit of that without expensive and major mods to gearboxes and diffs.
The larger the diameter the larger the 'Lever' is created loosing valuable power and torque at the rear wheels and stressing the rest of the drivetrain.
So unless you go to 4.10 diffs you are loosing too much. If you tow a lot it's an even bigger strain.
There is also a thing called 'Unslung Weight' and that is the bigger the tyre and rim the obvious heavier they are. That unslung weight has also got to be then 'Slung' around by your gearing adding further stress and strain. It's the same physics applied to slinging a 3Ltr Billy can full of water around in circles, and then doing the same thing with a marginally larger 5Ltr Billy can. The difference in effort is greatly increased and like the drivetrain on a vehicle, that extra stress needed on your effort (power & torque) and the increased strain that puts on your fingers, wrist, elbow and sholder joints (diff,drive shaft, splines, gearbox), also extra strain on your hips thighs and legs to maintain balance (steering gear, sway bars, track bar etc) takes it's toll and you tire much quicker.
I'll get off my soap box now ... Just my 2 bobs worth on the subject mate .

At present I can see you are heading down the right track to get the temp drama sorted.

Keep us all posted on the progress mate.

Cheers,
Reg

 

Well, got my truck back today, rather unexpectedly. Anyway the diagnosis is as follows.

The hottest he could get the truck, working it up a few large hills etc, was 98' Degrees. It averaged 80' Degrees, so his testing instruments told him. So basically, the Banks Dyna Fact gauge, when it reads 240F is really reading 98'Degrees at worst, or 208F. That is how far out the gauge is. I know it is hotter than your trucks but he believes the crap aftermarket transcooler is increasing it the extra temperature. No more BANKS gear for me, even though it came with the truck.

I have purchased a TRU COOL trans cooler for the truck. This time it is a quality one. Its 568mm x 212mm x 30mm to sit directly behing the grill with a thermo fan attached as well. That should bring the temp right down. So, after all that, a good result.

So I guess I will be replacing the gauge at some stage now, along with getting other ones. The guys said to me that the only real way to get the temps right down is to put the billet converter in and reduce the friction etc, but a cost of $1850. Sadly enough as I was leaving the gearbox shop one was coming in for a complete rebuild. It had been tilt trayed all the way from Fraser Island, 3.5 hrs away. Poor bugger.

So in summary, gauge was reading wrong. Looks like the US bros were right with there opinion of the faulty equipment at hand. Thanks again for all the advice fellas. Its invaluable. I can now focus one fixing the HPOP and bellow up pipes along with the other mods.