Delica Canada | Mitsubishi Van Club

My transmission fluid is a lot darker than I had previously thought from just looking at the dip stick, so I'm guessing it may be original and at 145,000km...

The manual has a procedure for "fluid change" (pan drain) but not for a complete flush... I didn't even see a service interval for the transmission fluid. I was planning on doing a full flush/change, but now I'm wondering if it's advisable with this transmission?

I did read about 5 pages of search results w/o finding anything specific.

There's no issue with doing a full flush. If your fluid is *super* sludgy there's the risk the new fluid will dislodge something nasty, but if it's that sludgy you have other problems.

Here's how I change/flush fluid: Drain fluid from pan, refill with new fluid through the dipstick hole. Disconnect the oil cooler rubber hose at the front and aim it into a bucket. Have someone else start engine and shift the gear selector through the range (with foot firmly on the brake!) while you watch the fluid coming out of the oil cooler line. When the fluid changes colour to the new, fresh fluid, shut off the engine, reconnect the cooler line, and refill the gearbox.

Check fluid level with the engine running, fill it to the "cold" level, take it for a drive and re-check that the fluid has risen to the "hot" range. If it's too high or too low, correct it.