2012 Pb Challenger Auto and 5th gear?

[Syten84]

Hi guys, I am hoping someone might be able to help with some info here but basically I don't believe my auto is actually going into 5th, even cruising at 100kmph on the highway if I slide it from D across to sports mode it won't shift any higher than 4th. Going between the two the revs don't even change to indicate a change in gears.
Not sure if it is going to be case of taking it to a trans specialist for a going over or its something else.

Any help or information would be much appreciated

[old Jack]

Chances are that is because it is already in 5th gear!
At 100kph with standard diameter tyre the following is correct;
4th gear Torque convertor locked 2650rpm, unlocked 2950rpm.
5th gear torque convertor locked 1950rpm, unlocked 2450rpm.
When you flick from Drive to Sport Mode the gear which you are in should be displayed on the dash indicator.

OJ.

[Syten84]

Cheers OJ,

Currently at 100kmph it generally sits around 2600rpm which by your post indicates to me 4th gear locked tc.
When I do slide across to sports mode the indicator on the dash shows me 4th.
I did record an example but realised I have no where to host it.
Cheers again

[old Jack]

So will it go into 5th if you manually go up a gear?

OJ.

[Syten84]

So will it go into 5th if you manually go up a gear?

OJ.

No, the highest gear it allows me to select in sports mode is 4th. And at 100ks the revs don't change between sports mode 4th and Drive

[old Jack]

Are you able to downshift to 3rd manually?

OJ.

[Syten84]

Yeah I can drop back to 3rd and come back up to 4th with the sports mode. Just not 5th

[old Jack]

Ok so we have proven the sports shift works in both up and down selections.

When did you first notice the problem?
Has any work, servicing, modifications been done on the car recently?
Have you been off road recently and did the problem happen after?
What colour is the ATF, when was it last changed?

OJ.

[Syten84]

Yes the sports shift does work in both directions, to be honest I actually just thought I had a 4spd box even though everything I read indicated A 5spd.i have fitted an idrive throttle controller and a chip it egr block module. I haven't yet tried unplugging them to see if it changes anything. I did an engine oil and filter change roughly 5,000km ago and drained and refilled the ATF (roughly 3L at that point)
I havent been off road with it since February
I can't actually pin point when this began to occur as I dont often use the sports mode unless I am off road in particular going down hills

[old Jack]

What ATF did you use?
Is the ATF level correct?
So have you ever seen 5 displayed on the dash?
Have you ever seen the RPM at 1950 at 100kph?
Is the car a grey import?
If you lift the bonnet, on the cross frame just above the lefthand headlight there is a data plate. It will list the Transaxle specification, it should be V5A5, does your car have this?

If you can confirm a 5 speed trans is fitted and the ATF is the correct type and level, then my thoughts are a faulty Low Range switch, if the switch was faulty it could be sending a "low range" signal to the AT ECU and then the ECU will not permit the trans to go into 5th gear. There are 5 switches on top of the transfer case, the low range detection switch is the forward switch on the righthand side, the wire colour is Blue with a Red trace, plug is brown in colour and there is a black sleeve over the wire between the switch and the plug. You could just try disconnecting this plug and see if the trans will shift into 5th. Switch B in the attached diagram.

http://faq.out-club.ru/download/pajero_sport_2008/maintenance/Service_Manual_2009_2011/img/23/AK602115AC00ENG.pdf

OJ.

[Syten84]

Ok, so I am using Royal Precision Lubricants Syntrans mv. A fully synthetic trans fluid.
The placard reads v5a5a and i am about to test the low range signal theory. Thanks for your assistance so far

[Syten84]

oj mate you're worth your weight in gold. Unplugged it and did a quick run up the high way. 5th gear is running great getting the approx 2000rpm at 100ks with 5th showing on the dash in sports mode.

The next question, fixing it? Is leaving it Unplugged an option or will that just give me problems with something else?


Glad the problem is identified.

"My weight in gold". A big price to pay, would have been cheaper to by a new car!

100kg at $84,000 per kg is $840,000, not bad for 10 minutes of my time! Lets say you owe me a beer if we every bump into each other.

I would say it is ok to run unplugged but not use low range until the switch has been replaced. There must be a reason why MM do not want the auto to go into 5th in low range, the manual transmission can be used in 5th gear low range.

OJ.

[Syten84]

Thank you very much, and I'm good for the beer. I have family in Adelaide I am over due to visit. But it's going to have to wait for now with this virus and all.

I'll look into replacing the switch as soon as possible and avoid low range for now

[Pixie_au]

Even better...$8,400,000

[emoji106]



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