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Auto box shift problems up and down the box

muscat_diver

War Hero
I run a Dodge Durango with 5.7 Hemi. Need a big car for pulling boat trailer and camping trailer in to desert - all recreational use. Had it for 5 years or so from 100km to now 220km. Shifted from preventive to condition based maintenance due to car value dropping. Drive it 70km per day, highway, 80 kmh on cruise control, regular oil and filter change, Started noticing that on acceleration it went up to 2,000 rpm then instead of changing up it held the rpm in lower gear. To get the auto box to change I had to take foot off the gas. No noticeable problems on change down until last two days. Each time the engine has cut out when downshifting into second or first gear when I slow for speed bumps or roundabout, Engine cuts out so does power steering, quick shift into 'N' and she fires back up but this will be a problem one day with either no space to manoeuvre of 3 ton of boat pushing me. Stealers are prohibitively expensive so will use local garage but grateful for advice on possible areas to trouble shoot rather than the lads start replacing parts willynilly hoping to hit on a solution. Many thanks for advice
 

RBMK

LE
Book Reviewer
Find a good local autobox specialist.

Sounds like you have a valve failure in the shift system. the old adage applies "no user servicable parts inside"

PS IIRC it's a Mercedes autobox.
 

Helm

MIA
Moderator
Book Reviewer
Could also be a clutch band slipping if they are used, as said take it to a grown up, unless you know what you are doing.
 

goodoldboy

MIA
Book Reviewer
Dip the transmission fluid to see if it's clean or if it's dirty brown with a burnt smell. If it's clean then the autobox may be alright and you could have an electrical problem. Worth a two minute check...
 
Is that the same engine and box as used in the Jeep 5.7 Grand Cherokee? If so,as goodoldboy points out, a fluid check/change might do it. Mate had said Jeep, and we changed the fluid, which fixed it. The fluid looked OK-ish, BTW.
 
I run a Dodge Durango with 5.7 Hemi. Need a big car for pulling boat trailer and camping trailer in to desert - all recreational use. Had it for 5 years or so from 100km to now 220km. Shifted from preventive to condition based maintenance due to car value dropping. Drive it 70km per day, highway, 80 kmh on cruise control, regular oil and filter change, Started noticing that on acceleration it went up to 2,000 rpm then instead of changing up it held the rpm in lower gear. To get the auto box to change I had to take foot off the gas. No noticeable problems on change down until last two days. Each time the engine has cut out when downshifting into second or first gear when I slow for speed bumps or roundabout, Engine cuts out so does power steering, quick shift into 'N' and she fires back up but this will be a problem one day with either no space to manoeuvre of 3 ton of boat pushing me. Stealers are prohibitively expensive so will use local garage but grateful for advice on possible areas to trouble shoot rather than the lads start replacing parts willynilly hoping to hit on a solution. Many thanks for advice

I see you’re in need of my expertise. After reading your post and using my years of extensive knowledge I suspect the problem may be that the fücking fücker’s fücking fücked.

Hope this helps.
 


sell it....
 

OneTenner

LE
Book Reviewer
Fluid & filter change interval is quite short - three or four years depending on specific 'box and IIRC about 35 - 45k max mileage interval. Make sure the torque converter is also being drained, it holds ~3 litres. If it isn't drained, you only get 2/3 of a fluid change. A fault code read on the engine & transmission will give any further pointers but at this stage, i'd go for a transmission fluid change as a first (and possibly cheapest) stage.
Note that the fill level has to be checked with the engine running, with it stationary you could end up with a few litres too little in the 'box - which WILL cause damage.
It's a shitty messy job which needs doing correctly.
 
ATF full drain and replace as others say. Make sure you use correct spec fluid. If accessible change/clean the filter too, often a mesh strainer

You'll need to run engine and shift gears, then check fluid level when warm

For model specific advise, join a Dodge tech forum
 

Joshua Slocum

LE
Book Reviewer
How long do those autoboxes last normally ? with a mahoosive engine like that it should not be worked to hard ?
can you not get a service exchange box fitted
 
You cant do a fluid and filter changes at home on most modern autos , some have to be done engine running and I have heard that some have to be done in drive , wheels off the ground,but you could always buy one of these
 

OneTenner

LE
Book Reviewer
You cant do a fluid and filter changes at home on most modern autos , some have to be done engine running and I have heard that some have to be done in drive , wheels off the ground,but you could always buy one of these
No. they're snake-oil and many auto boxes require a filter change which in most cases is in the sump pan, I'm not aware of any auto box that needs to be level checked in drive with the wheels turning, in any case, the vehicle in question most likely has a Merc. derived 'box which *could* be done on the ground - not ideal, but possible.
When I was self-employed I used to do LandRover Auto 'box fluid & filter changes on the floor, they were ZF boxes and a bit more of a pain than the Merc. ones, still doable though. Like I said earlier, it's a shitty job but it needs doing properly - which means filter and fluid.
 
Could be something simple like just cleaning the contact points in the auto box .. a good mech will do it in 30 mins
It’s come up a few times now. MB shifters are weak. Get a check done at a specialist. I haven’t had a MB for a few years, but had shifting issues and my local specialist advised looking for a new shifter (which seem to have cross-use among many variants). Spilling drink into the flat box could cause this weakness. I binned the car.
Good advice above, get it checked.
 

OneTenner

LE
Book Reviewer
How long do those autoboxes last normally ? with a mahoosive engine like that it should not be worked to hard ?
can you not get a service exchange box fitted
It's a big engine but 'lazy', the 'box will be matched to the engine torque levels so there shouldn't be any premature wear on the mechanical components. ZF 'boxes typically have a fluid 'life' of 6 - 10 years / 90 - 150k miles dependent upon type & usage, Merc. 'boxes are 3-4 years and 35 - 45k miles, again dependent upon type & usage.
ZF 'boxes are hardier but not as refined - good towing boxes, Merc. 'boxes are smoother but more likely to have issues, also can get into a 'race condition' with the adaptive learning, not as good as it sounds, gearchanges can be harsh and unpredictable.
Don't get me started on the Jap 'boxes used by Ford & JLR...
 
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