360 HEAT EXCHANGER DELETE/BYPASS

There's a reason the heat exchanger was included in the design of the 360. It serves two important purposes:

1. It pre-heats the transaxle oil, making shifts in first and second easier.
2. It cools the oil during heavy operational use, like track, or going to the grocery store the long way.

Removing the heat exchanger would be like removing your pancreas. You can live without out it, for a while, but it will be missed.

 

I'm definitely doing this bypass next time I have the intake manifold off. I'm going to add an external gear oil cooler with a thermostatic valve.
I'll probably run -10AN lines and a thermostatic valve (165 or 185 degs) like this https://www.improvedracing.com/high-flow-engine-transmission-oil-cooler-thermostat.html
and whatever cooler I can fit.

To me it's not worth it to keep the exchanger. They can fail at any time and how will you know?
The cost benefit ratio is:

Faster warming of gearbox oil
vs
Silent destruction of gearbox internals worth tens of thousands of dollars

 

I removed my heat exchanger 10 years ago. Have had no problems. But I do live in South Texas and do not track my car.

 

I bought my 07 430 in Dec 09 with 2015 miles. It never shifted that well, especially dropping down into second. Three years later, shifting was terrible. On it's annual service, the heat exchanger had failed. I feel it fried all the internals in the gearbox. A ten year debacle ensued. 4 different mechanics. 10s of thousands of dollars. Finally ended up at F of Ft Laud 2 years ago and bought a brand new gearbox.
I find it outrageous that this part can be so fragile. Not sure how this helps the conversation. I guess I'm letting others know this part is suspect.

 

There is a reason it is a "heat exchanger" as opposed to a "trans oil cooler." The main reason is to bring the heat of the gearbox oil up to temp as the water heats up faster. Simply swapping out the exchanger for a new one is easier than deleting it and it's likely that it will outlast your ownership of the car.

Also, yes, these units are failing everywhere, but it's more because of the age of the car than it being an unreliable part. Swap it out, and the problems go away (don't forget to flush out the trans and cooling system a million times, should it break).

Finally, it makes no difference on the miles. It's time. Many gearbox oils are not compatible with yellow metals and it eats away the syncros and the exchanger. I've now seen both fail (sometimes the syncros before the exchanger). I've now had personal experience with 10K mile cars failing and 95K mile cars with original exchangers doing just fine. The difference was the 95K mile exchanger was 10 years ago and the 10K mile car was recently. Any 360 you purchase at this point in time, without recent records of a replacement having been done, needs a new exchanger, period.

 

I have cured this on two cars, just by switching to Redline NS. Yes the exchanger will trigger syncro issues but I've now revived two bad transmission by switching and flushing multiple times with NS.

When I bought mine, the transmission was "toast." Grinded loud on every gear. Terrible. Dominick recommended I try the NS fluid with a friction modifier and told me it would be a slow improvement, if it works. He was right, it was slow - took about 4-5K miles. But 30K miles later (I drive everyday), it runs like new. Upshifts, downshifts, it screams at 85K miles.

Just did the same on my friend's 30K mile 360 with a recent heat exchanger failure. Started grinding and not shifting. I had the dealer flush it with Redline twice, and it's back on the road!

My point is that anyone who is experiencing transmission trouble after a failure should try this first. Once the syncros start working, one at a time, you could be home free. It may not help every time, but I'm 2 for 2 right now - both following dealers prescribed new gearboxes.