G'Day OzBargain, I own a 2009 Holden VE Commodore International (3.6L V6) with a 4 speed 4L60E transmission.
I've recently been having transmission issues, particularly with erratic shifting behaviour, more specifically:
On takeoff, the car seems to skip 2nd gear entirely, and will only shift out of 1st gear when I rev high (around 4k revs) and let off the accelerator, and only then it will shift into 3rd gear.
When cruising at around 70-80km/h it will slip into 2nd gear (as reported by OBD2, but revs drop to 500rpm which is weird), unless I hold the throttle to maintain some revs. Normally at this speed it should be sitting in 3rd or 4th gear, but the car also seems reluctant to shift into 4th, but has done on occasion.
Today I took the transmission sump out and drained the old fluid (which was a nightmare, (profanity) GM and their (profanity) design) and inspected (and cleaned) the sump for any metal parts, of which there were none.
Does anyone have any advice on next steps to diagnose the issue? For reference, I'm a uni student who doesn't have much in the bank.
This car also guzzles petrol (even more so now), so I don't really want to put a new transmission in this thing, and I'd rather scrap it or sell it as a fixer upper. It also costs me an arm and a leg to insure as a P plater with a V6.
I'd also like to get a new car because I've had too many issues with this thing, and the running costs are high. My budget is around $10k and I want something manual, that is DIY friendly, because I'm passionate about working on my car and driving it for fun.
Put it back together and trade it in on a Toyota. They're very easy to work on, not that you'll be doing much more than basic servicing.