Failed RE4 after upgrades.

Not a happy Easter camper!

Was heading up to Kalbarri for the weekend as a shakedown trip after spending a ton of money on upgrades including HD Flex Plate Low stall torque converter, stage 2 valve body along with ZL30 Turbo/Tune intake mods etc.

Only made it about 175km out of Perth and I was just cruising along at 110kph, when I heard a thud from the trans, she dropped itself out of overdrive and was making strange noises.

I had noticed the trans temp gauge hadn’t moved from 60° but put it down to being a cool 15° morning and an easy hwy run. However the trans felt a lot hotter than 60° when I felt it from underneath! The fluid on the trans dipstick was hard to see and appeared to be clear. But with some time to think now, perhaps it was just residue on the dip stick. I couldn’t see any obvious leaks anywhere.

No reverse gear at all, and not game to keep trying to drive it forward. Tow trucked it back to the mechanics workshop 😞
I’ve done less than 500km since the trans was done, and she was driving beautifully before this happened.

I am supposed to be heading off on a 5 week remote trip on 7th May, and this was a shakedown trip to make sure everything was good. Glad I’m not in the middle of the desert at least!

Attachment 85229

Bugger. Hope it gets sorted pretty quick.

If you were running with TC locked that would account for the low trans temps if the temp sensor is located at the cooler outlet banjo.

Be interested to know what happened. The RE4 transmissions have very few issues.

Sorry to hear this. Fingers crossed for you.

Quote:

---

Originally Posted by jff45

If you were running with TC locked that would account for the low trans temps if the temp sensor is located at the cooler outlet banjo.

Be interested to know what happened. The RE4 transmissions have very few issues.

---

The temp sensor is pre-cooler, but it was a pretty easy run, just cruising and not many hills between my place and where it failed. It’s only done around 500 very easy kms since the upgrades. I’m thinking it’s going to be a shitfight, but hoping the workshop does the right thing in investigating what failed and rectifying it ASAP. I also have a wholesale autos lockup switch installed, I’d used it maybe 15 or 20 minutes prior to make sure it worked, only had it engaged for about a minute as it wasn’t really required. The TC was having no trouble staying locked without it.

They already mentioned on the phone when I called them on the side of the highway, about the extra torque I’m running, which sounded to me like looking for excuses already. The extra torque was the whole reason for the trans upgrades and I know how I’ve driven it, should be nothing failing with the easy km’s its done.

I was running it on tune 1 the whole way from home, which was max 538nm on a hub dyno. Tune 2 was 634nm at the hubs. I could understand something breaking if I was flogging it up a dune or driving like a racer boy, but it was just easy cruising with the traffic flow.

I run a warmed 150kw TD42T in front of my RE4 with stock TB45E J6 TC and Nomad valve body. I tow 2.7t caravan no problem.
I rebuilt a spare RE4 years ago with extra clutches but it’s still sitting on the shelf waiting for the current one to give up.

If I had to guess I’d say something wasn’t put back together properly but it’s likely to not be anyone’s fault as usual..

Quote:

---

Originally Posted by jff45

I run a warmed 150kw TD42T in front of my RE4 with stock TB45E J6 TC and Nomad valve body. I tow 2.7t caravan no problem.
I rebuilt a spare RE4 years ago with extra clutches but it’s still sitting on the shelf waiting for the current one to give up.

If I had to guess I’d say something wasn’t put back together properly but it’s likely to not be anyone’s fault as usual..

---

Everything I’ve researched prior to doing the turbo/intake etc mods, indicated it should be no problems with a JD trans stage 2 valve body, destalled converter from Allfast in WA and a HD Flexplate. The trans hadn’t been put under any sort of hard driving in the short time since it was done.

When it went, the missus and I both heard a distinct thud from the transmission and I can only assume somethings let go internally. It immediately dropped out of overdrive and I pulled up within 1k or 2 in a safe spot off the highway. The wait to find out what’s gone wrong is driving me nuts! I looked at my trip log of the day it went and my average speed was 100.9km with a max speed of 122kph briefly when I overtook a road train. When it let go it was only on light throttle maintaining cruising speed at 110kph. We were loaded up, but not towing anything.

My concern now is finding out the damage and how quickly we can get it repaired. I’m at the mercy now of the workshop and just hope they are honest in their findings if it’s due to incorrect assembly or faulty parts etc.

Just curious, was the TC manually locked during shifts?

Quote:

---

Originally Posted by jff45

Just curious, was the TC manually locked during shifts?

---

Never engaged while shifting gears, I’d only used the lockup switch once to see if it was working after the mods had been done. Had it engaged for about a minute or so around 15 or 20 minutes prior. I’ve rarely used the manual lockup since it was fitted years ago, as I find the trans automatic lockup did the job ok anyway.
Only find it useful to stop running away on long downhill runs. Maybe if I towed, I’d have used it more often.

Bummer mate that’s not good news, let us know how they deal with this.

The results are in!
4th Gear was destroyed due to a lack of lubrication. They tell me that one of the FMIC pipes was pushing against the trans cooler hose and squashed it to the point it was severely restricting flow. Lucky for me that they also fitted the Fabwitz front mount intercooler and pipework.
Its good to see a shop that stand's by its work ethic and accepted full responsibility for the repairs. They said they'll do their best to get it done by the end of the week. Thats good enough for me, and I'm a happy camper again.

So best to keep this in mind for those mounting their own FMIC. Make sure none of the trans lines are getting squashed! It's an unusual one and not something they've had to deal with before. Hopefully this will be the end of my troubles with the auto.

Good result! That also explains why your trans temps weren't moving, no flow through the cooler. The return from the trans cooler lubricates the rear.

Quote:

---

Originally Posted by jff45

Good result! That also explains why your trans temps weren't moving, no flow through the cooler. The return from the trans cooler lubricates the rear.

---

I had suspected there was no flow, but couldn’t work out why. I was thinking a stuffed pump, or low fluid or something. I’ll ask them in more detail when I pick it up, but was told on the phone it was the FMIC pipework to the turbo. It was the first time they have fitted the Fabwitz FMIC, and told me at the time it was a painful exercise. Mistakes happen, but I’m glad it happened now and wasn’t my doing. It would have been a nightmare to deal with in the middle of the Simmo where I’m heading next month.

I have my trans temp gauge in the inlet to the cooler, but am now thinking in the pan would have given me a true reading and may have alerted me to the problem sooner. Something to think about for those installing trans temp gauges.

Quote:

---

Originally Posted by stevemc181

I have my trans temp gauge in the inlet to the cooler, but am now thinking in the pan would have given me a true reading and may have alerted me to the problem sooner. Something to think about for those installing trans temp gauges.

---

I’ve found the most practical spot to fit the sensor is in the outlet banjo bolt where the TC pumps the fluid to the cooler. The inlet to the cooler will have pretty much the same temp but the banjo is an easy fit.
I prefer to read the temp where it’s hottest so I can lock the TC when towing to bring it back down.

Attachment 85244

Quote:

---

Originally Posted by jff45

I’ve found the most practical spot to fit the sensor is in the outlet banjo bolt where the TC pumps the fluid to the cooler. The inlet to the cooler will have pretty much the same temp but the banjo is an easy fit.
I prefer to read the temp where it’s hottest so I can lock the TC when towing to bring it back down.

---

I had no hope of fitting the Redarc 1”4 inch sensor in there. I also have a Redarc 1/8” sensor but the probes are just too long in that location. I think with no fluid flowing they’d suffer the same fate.

Yep, it needs the VDO short sensor

She’s all up and running again :)
They ended replacing the transmission with a refurbished unit, also a new torque converter and factory cooler. It was apparently all in a hell of state due to heat and bits of gears through it.

Now the fluid is circulating correctly, I can see the trans temps are higher than I’d like. It easily hit 100-110°C around town. Given my short time frame before I head off on a remote trip, I’m going to throw a cheap cooler and fan from Repco in tomorrow. Should help at least having a fan. I’ll source a better cooler on my return if required.

She all seemed to perform well on a 200 km run I gave it today, so hopefully I’ll have no further issues.

Remember that you’re reading the fluid temp pre cooler. It’s almost certainly under 100C by the time it gets back to the trans.

Quote:

---

Originally Posted by jff45

Remember that you’re reading the fluid temp pre cooler. It’s almost certainly under 100C by the time it gets back to the trans.

---

I threw another cooler in series with the factory cooler. Dropped the temps a bit, hottest she got was 105° after a long uphill section heading out of Perth, and seems to sit around 80-90° on the highway. The fan doesn’t seem to do much, so not sure how she’ll go in the soft slow dune country.

I’ve got another sensor coming that I’ll throw on one of the pan bolts as well. What’s the usual pan temps on these?

Ideal operating temp is generally considered to be around 80C but with low stall TCs and/or TC lockup, the temp being pumped out by the TC is often lower.
Mine can get down to 65-70 pre cooler on the highway.

I’ve thought about getting the fluid direction controlled by thermostat so it only goes through the cooler over 80C but I haven’t got around to it.

Quote:

---

Originally Posted by jff45

Ideal operating temp is generally considered to be around 80C but with low stall TCs and/or TC lockup, the temp being pumped out by the TC is often lower.
Mine can get down to 65-70 pre cooler on the highway.

I’ve thought about getting the fluid direction controlled by thermostat so it only goes through the cooler over 80C but I haven’t got around to it.

---

They were telling me it will run hotter with the low stall in it? I thought it would be cooler as well due to not as much slip? I think 80° is ideal temp in the pan?

Quote:

---

Originally Posted by stevemc181

They were telling me it will run hotter with the low stall in it? I thought it would be cooler as well due to not as much slip? I think 80° is ideal temp in the pan?

---

You should be running above your stall speed on the highway so I'd expect it to run cooler because of that. I use the stock J6 TC which stalls around 1950-2100 and with 3.9 diffs it doesn't often get over that at cruising speeds.
I run at 1850 rpm @ 100 km/h with TC locked and trans temps coming out of the box just plummet.
I run a big Davies Craig cooler in series with the factory TB45E cooler which, btw, is about half the size of the stock ZD30 cooler so my trans temps are always too low unless I'm towing the caravan.
I've had my trans temp gauge hit 120C on one occasion but that doesn't worry me as it's pre cooler temps and I run full synthetic fluid. It drops quickly when I get the chance to hit the TC lockup button.

The factory trans temp warning light comes on at 140C but most agree that that's already too hot for mineral fluid and clutch damage has already started.

@jff45 Thanks for the info. I’ll keep a close eye on the temps for this trip and see how she goes. I’ve got about 10’000km to cover, in a variety of highway/desert terrain.
When I get back I’ll have a look and see if I can shoehorn this in https://www.tuffcarparts.com.au/aero...ansmission-oil

I’ll also change the fluid out to synthetic as they used a Dex3 mineral fluid in it.

You can always manage trans temps with the manual TC lockup. Just engage it when not under load and avoid loading it once locked. You'll see the temps drop quickly.
There are those who are happy to keep their TC manually locked during shifts but I avoid it as does the factory behaviour.

Castrol TransmaxZ is considered the best trans fluid but it costs. I use Nulon multi-vehicle synthetic. The important thing is that they flush the whole trans with it, about 12 lts, not just the 4.5 lts in the pan.