can u pls tell me how to remove this harness from the tranny!? [email protected]

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So I was about to make an appointment for my X5 at local indy. I got the trans failsafe error. The x5 badly jerks at about 20mph and I noticed if I try to go faster it stays in the same gear. I noticed my cruise control no longer works. I tried the reset cluster fix that didn't work. Any idea what the average cost I should look to paying its at 120,000 mile. I'm keeping it garaged up during the week and take it for drives around the neighborhood to get the engine warmed up and tires from going bad on the weekend. I put like 30 to 40 min drive time taking slow and steady.
Headliner material starting to fall down too. I bought some 3m 77 spray going to try and fix it.

There are two entrenched camps. One is based on that BMW states the fluid is a lifetime fluid and/or they believe changing the fluid will release contaminants that will cause future transmission problems.

I am in the camp of change the fluid and filter every 40,000 miles which I have done since it was new. I have had no transmission problems. Only other thing I have done is I installed Dinan transmission software at about 1,500 miles. I have 118,000 miles on my modded 4.6. I am in the change camp because of a long discussion with a ZF transmission expert of 20+ years experience repairing transmissions that advised there is no trans fluid that will last a lifetime and to change the fluid and filter about every 40,000 miles. And that it doesn't matter if you have never changed the fluid and start doing so it is still is best practice. The filter is there to pick up contaminants and metal stuff sticks to magnets in bottom of the pan. If the fluid has never been changed since fluid stays in the torque convertor unless the transmission is flushed rather than drained, I would change fluid and filter, drive it 100 miles or so and change fluid and filter again. I use only ZF because it was the fluid the mfg. used. I see no reason to try anything different.

Definitely change fluid. I took the automatic trans out of my 323i at almost 300k miles. It still works I just wanted to put a manual in it for autocrossing. I changed the fluid in it.

Change the fluid regularly if you want an automatic to last.

Simplest approach is would you run your motor and never change the oil? Well of course not. Well think about this then. The trans SHEDS particles by design. The clutches give off material over time so these particles will become wedged in the filter.

So not only would you be robbing you motor of fresh not degraded oil you would be not changing the oil filter which you know gets clogged over time.

So following that logic its a no brainer that the fluid and filter needs to be changed at some point in your automatic transmission or it WILL fail. I cant promise it will last forever or x amount of miles from changing the fluid. But I can promise it would of made it further miles wise if you had of changed the fluid.

Heck you can see a difference in steering just by changing the TRANSMISSION FLUID out in the power steering from time to time. But you wont do the same for your transmission which works a bazillion times harder than the power steering does?

Again I don't see how there can be any argument against changing the fluid if done correctly.

Its actually not a bad idea around 200,000 miles to replace all the solenoids. They do wear out but the real reason for swapping them out (not required but if you love maintaining things its not a bad idea) is they become clogged with materials from the clutches and such. I have found all kinds of bits lodged in them and the bores they slide into on different transmissions I have built.

Also on the jerking when shifting this can be caused by particles stuck in the solenoids like I mentioned above and by the bores being scared that the solenoids work in. They bind up and the transmission commands more pressure to compensate and then the solenoid frees up thus the harsh shift.

A common problem from this for instance the 4l60e transmission used in gm products. Its what we call the slam shift. If you drive for a few miles and then come to a stop and then take off when the transmission goes to shift from 1st to 2nd it will shift so hard you will think someone rammed you. This is from the aluminum piston in the bore seizing the transmission is commanded to up pressure till it finally breaks free.

GM made a TON of money off this flaw selling reman trans replacements to customers. All they did was replace the valve in the defective transmissions and then sell them back to the customers for $2000 plus dollars. Nice racket.

Anyways start with a fluid and filter change then move up to a valvebody replacement is how I would go about it if everything else seems fine and I didn't know how to actually diagnose the problem fully. Its the cheapest route. If you do have to have it built at least you already have a new valvebody for the new trans :)

Don't let anyone do a "flush" on it. Just a normal fluid and filter change is what you want. On a normal maintained trans a flush can stir up problems but on trans that has never been maintained correctly that's just asking for it.

Crowz, what you say about the cause of the slam makes perfect sense. But what explains why we don't get the slam in sport mode (in some cases) or in manual mode. Surely the same hydraulic actions are taking place, regardless of the shift logic?

Actually not at all. When in sport or manual mode several factors are normally ignored or handled differently.

The follow is all made up numbers to explain how this works not actually psi values.

Lets say it takes 20 psi to achieve x function (lets call it shifting) under normal driving conditions not in sports mode, manual or floored just normal grocery getting driving.

Ok lets say we have valve sticking and causing harsh shifting in this scenario at 20 psi applied pressure. When the trans doesn't respond at 20 psi the pressure is raised to 40, 60, 80 or more till the trans does respond. Thus when it does free up it slams into gear.

Now when you floor it or use manual or sports modes what exactly is the difference in these modes vs normal? Pressure. Nothing else but pressure. Line pressures are increased to cause firm, quick, hard shifts which actually is how an automatic should work all the time anyways but customers wont tolerate that kind of shifting all the time so manufacturers run low slipping pressure to ease into gear to make the customer happy.

So now that we are in sport/manual/floored the transmission is commanded to use 40, 60 or 80 psi all the time for all shifting functions.

Well that was the pressure that was needed to free things up before so there is no sticking aka no problem to start with in those modes.

This is all theory as to what is causing your shift issues. Without testing I cant confirm for sure that's what is happening I am just giving examples of what COULD be happening based on how an automatic transmission works.

I think this is more of a problem found in the ZF5HP24 in V8 X5. Never heard of the GM trans doing a Slam shift when coming to a stop and then accelerating before the X comes to a complete stop.

For the ZF5HP24, electronically controlled overlap gearshifts are used on all shifts except First to Second. First is the only gear with a freewheel clutch, since at the low speeds the first to second change occurs, the accuracy of the data from the input/output speed sensors is limited. All the shifts are completely closed loop controlled so that a consistently high shift quality can be guaranteed through the service life and production tolerances. Conventional 4-speed transmissions use just two solenoid valves (on or off valves) for gear selection, with the old clutch pack being disengaged before the new clutch is engaged. A simple truth table of the solenoid valves state would immediately indicate the gear selected. This transmission uses five pressure regulators and three solenoid valves and a simple truth table would not indicate which gear is selected. This is because the pressure regulators are not simply “on or off’, but allow the pressure to the clutch packs to be balanced to give the appropriate gear. Overlap shifts mean that neutral is not selected between gears. Pressure is applied to the “next gear” clutches as pressure is reduced on the “old gear” clutch packs. This requires a high TCM processor overhead as the two clutch pressures must be balanced throughout the gearshift to give a high shift quality and protect the transmission from damage. The advantage of this system is that drive is not interrupted, torque is always applied to the wheels throughout the gearshift and greater shift quality is possible. Since there is no neutral between gears, the gearshifts are no longer hydraulically protected. Hence, the TCM monitors the change characteristic for anomalies. If the shift does not match the specified characteristic (rate of change of input and output speeds etc.) then the gearshift is aborted to prevent transmission damage.

Overlap shifting is only possible using a high speed communications link to the engine management system so that shift energy management can be closed loop controlled in real time. Shift energy management allows the transmission to control the engine output torque during a gear shift, so that excess power is not dissipated in the transmission friction elements during the shift. The functions of shift energy management are: 1. Increasing the transmission life by shortening the slipping time. 2. Improving the shift comfort by reducing the step change in torque caused by the gearshift. 3. Limiting the maximum engine power transferred into the transmission.

The slam shift issue is due to a pressure issue within the trans. This could be from a scored piston valve in the valve body, broken o-rings or a drum that has cracked and is not allowing the clutch pack to maintain pressure.

i recently had similar prob with my 02 4.4 auto trans with 119000 i got a rebuilt solinoid kit on ebay $135?? installed them and a new wiring harness i did it n driveway took most of the WE!! NOW everything is shifting beautiful except if im at a dead stop and making a turn left or right the tranny is like coming outta gear and then slams into 2nd!! if im making the same turn and am in 2nd going to 3rd i have no problem at all!! im completely confused now!!any thoughts?? i see that upall nites seems to hav extensive knowledge with whit these hopefully they will reply

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