jeep grand - loss of power/ auto gears not changing up ?

[bunnykins]

just started to notice this last week, whilst driving, when you brake at the lights and you let go, the car
tends to move forward, but it seems very slow to move on and needs alot of pedal power to get moving

yesterday was towing our horse and going is fine, car auto box changes up over 50mph to 1.5k revs normal,
but going home this did not happen and the revs were about 1 k higher then normal on all speeds, idles ok.
[ as if the overdrive button is turned on ] but car not changing up. also near home coming to lights, found the
same thing happening, loss of power and needs alot of pedal to get moving.

any ideas ? anyone had this before ?

thks

p/s - seems to be when the jeep is full of passengers or when towing / could it be an intermittent fault somewhere ?

[Bishops Finger]

Are Birtys helping...

[dxmedia]

Torque convertor?

What's the oil level like in the box.

[bunnykins]

Torque convertor?

What's the oil level like in the box.

not checked it for over 2 yrs !! its very low, do u know where i can buy the mopar trans oil ?

i'll give the dealers a ring today.

[dxmedia]

ATF is ATF, there should be all the specs in the owners handbook. Pop down your local factors and get the fluid at a fraction of the price of Jeep.

Might be worth giving light house a call and putting a new auto gearbox filter in?  Give it a bit of a birthday in the process of topping everything up. No point doing any further diagnosis until you've the correct fluid level, if the torque convertor hasn't enough oil in it'll slip like hell (giving the symptoms you decribe too).

[bunnykins]

where is the torque convertor ? and does it need oil ?

i got the mopar and toped up the transmisson and i put in 3/4 ltr !

i got some gear oil from halfords and topped up the rear axle [ oil was quite clear so i thought that would be ok to top up, instead of draining it ]

i then managed to top up the transfer case with the Dex 3 , after i found step by step instruction videos on utube.
[ put in about 200ml so hope it wasnt too low to do any damage ]

couldn't get the front axle nut off as my allen key did not fit so leaving that for next weekend.

does anyone know what size allen key it is for the front axle ?

[dxmedia]

If it's the square hole, it's just a 3/8th drive ratchet straight in for the front axle.

The torque convertor is the auto gearbox version of a clutch. It's part of the drive train and it's filled with fluid when you fill the 'box.

If your torque convertor (gearbox) was low on oil, it would seem to be slipping when pulling away. Be unable to tow any weight, be poor (er) on fuel, not change gear correctly, be very harsh if it did change gear.

Any of that sound familiar?


Hows the car driving now it's got oil in?  Did you check the oil level with the box warm and the engine running?

[bunnykins]

If it's the square hole, it's just a 3/8th drive ratchet straight in for the front axle.

The torque convertor is the auto gearbox version of a clutch. It's part of the drive train and it's filled with fluid when you fill the 'box.

If your torque convertor (gearbox) was low on oil, it would seem to be slipping when pulling away. Be unable to tow any weight, be poor (er) on fuel, not change gear correctly, be very harsh if it did change gear.

Any of that sound familiar?


Hows the car driving now it's got oil in?  Did you check the oil level with the box warm and the engine running?

ok may have to borrow the tool from work.

well it just felt like the jeep is not moving off the lights without accelerating hard / yes towing as bad esp felt like the overdrive button was off as it didnt change up as usual. yes not changing properly, yes gear change was a little harsh..............all this sounds familiar !!

drove the jeep on sunday and gears now change up as normal and drives as usual, but not sure if it moves off alright, may have to take it on an incline
and check its ok.

i did check the oil when engine temp was warm and engine running.....only thing i thought strange was it was on min before and after i top it up ???
i didnt want to put anymore in just in case i've put in too much. maybe i need to check it again after a short drive.

thanks, actually gears now change so smoothly i hardly notice it changing.

[bunnykins]

right i have topped up all the oils and its still not changing up, also the overdrive button dont seem to work either.

it used to increase/reduce the revs when it is switched on/off. any ideas ?

there are any fuses to check ? or is ti something more like gearbox / transfer case prob ?

thks