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01 740iL Transmission problem

113K views 96 replies 52 participants last post by  arpad3 
#1 ·
I just bought a 2001 740IL that I love, but it seems to have a transmissin issue. The car has high mileage but a very good service history. It has been serviced by a BMW specialist. At about 40 - 50 mph, in drive, it feels like the tourque converter is trying to lock up and then releases constantly. There is a scraping type noise at the same time coming fron the transmission. If I drive the car in the manual shift mode it does not do this. It seems like it has a bad sensor or the tourque converter might be on its way out. Has anyone else had this same problem? If so , what was the end result? Thanks Bruce
 
#57 ·
Mike, I hope u replaced the fan blade and fan clutch. Those are super sensitive things on these e38s.. You wouldnt want to be reusing that same fan blade that was hitting ur fan shroud unless u want to expirence the Exploding fan syndrome, where it take out all the coolant hoses and dents ur hood
 
#58 ·
Oh yes!
Funnily enough I had somehow not heard of that until this happened, even though I have had BMW's since 1971, when we got a 30SA. Fabulous car, and my father and I were hooked.
I am actually debating removing the fan and clutch and fitting an electric one like my E36 and son-in-law's E46. I changed it on my E23 735 many years ago, and it was good. Wish I still had it.
Any ideas on this?
Mike
 
#60 ·
Ouch! If you already replaced the plastic ball valves, then the next issue is that the reverse clutch housing crracks. Pressure leaks, no reverse.
Hope not. I am sure that there is a plug in the casing that you can use to test the pressure. I should have this info somewhere and shall post if I have.
Best answer is S/H box. Check the ball valves and fit.
Mike
 
#62 ·
So after reading most of this thread (I admit to skimming) I wanted to add a comment or two.

1) Changing fluid on high mileage transmissions is not an issue if you don't go flog it immediately. Keep in mind that while a torque converter is essentially a pump it is also a centrifuge. Drive the car easy after a fluid change with moderate throttle and the heavy debris will be trapped in the periphery of the TC. Also change the filter to catch the big stuff.

2) Has anyone done a dipstick mod? Even if not for checking the level having the top accessible tube would simplify service.

-Mike O
 
#63 ·
So after reading most of this thread (I admit to skimming) I wanted to add a comment or two.

1) Changing fluid on high mileage transmissions is not an issue if you don'at go flog it immediately. Keep in mind that while a torque converter is essentially a pump it is also a centrifuge. Drive the car easy after a fluid change with moderate throttle and the heavy debris will be trapped in the periphery of the TC. Also change the filter to catch the big stuff.

2) Has anyone done a dipstick mod? Even if not for checking the level having the top accessible tube would simplify service.

-Mike O
I ended buying a used tranny for a few hundred bux. at this point i can almost care less :tsk:
 
#68 ·
i too just purchased a 95 740il with a similar issue. 118 on od. car makes a noise like it has a bad wheel bearing at around 30 to 40 mile per hour just rolling along no hard throttle. when the sound starts i let off on the pedal and it goes away instantly, but comes back soon after, but always goes away when i let off on gas. according to my bentley manual it states it's a driveline issue ie. driveshaft and components. i did hear an odd sound today going up an incline it made the sound and kind of slipped but no change in rpm. has anyone changed the driveshaft cv or center support bearing. the sound eminates from the center of the car on my right as if its a driveshaft issue. seems odd that a $61000.00 car can have such issues at 118000 miles I have a dodge ram with 199000 with no issues. this car is like a person that is too intelligent for their own good.:mad:
 
#69 ·
i have 2 so called indy shops near Me Steves european service, and Munks motors both have been in business for decades, but have no more of an idea of the problem than any of the post on here. only diff is they charge $80 per hour. so many intelligent owners and even more contradictions. why are expensive cars such a headache?:confused:
 
#72 ·
hello ladies... I am very disappointed with this thread about transmission noise I have a 1995 e38 with the "noise" at 30 to 40 mph so i read all the posts left for this this issue, and heeded all the advice. yet the problem was, as with any car, 14 to 19 years old is: fluid break down. there is no such thing as lifetime trans fluid... that is a total joke! remove the trans pan replace the filter fill it back up and what do you know problem gone... if your one of those that believe a BMW can with stand constant flogging that is a joke as well. i used valvoline max life total synth and a beck and arnley trans filter. followed the directions in my bentley manual (i would assume you all have a manual) and what do you know sound is gone. too many"whatevers" think they know the answer , or just like to give their opinion, don't go to the trans shop or your "indy" shop (a joke) this is a car that is worth 5000.00 tops why start out with a 3000.00 trans swap..... stupid!!! you need to understand if you buy an old BMW learn how to fix it. it is no different than an american car. torque convertors are all the same. BMW's cost upwards of $60 grand they are are not cars that break down. you must understand, that the average initial owner has a great job and can afford this car. as time goes by, usually the 3rd owner, all goes to hell...cuz no one keeps them maintained. if you are looking for help on bimmerfest you must love this car... common sense prevails.. " IT'S A BMW" not a CHEVY, or FORD. learn how to repair this beast. don't get HOSED by the so-called INDY shop. MY indy shops cost me 3000.00 to fix a simple problem because they wouldn't listen to the car owner. /(ME) 10 years ago lesson learned. don't buy something you can't fix.
 
#75 ·
dip stick mod/trans issues/noise

from what i can see, from doing my '95 740il v8 the fill plug is on the underside of the pan, not on the side of the trans as in some other models. so don't think dip stick mod works for '95 and up 740's and 750's. i have changed the fluid twice since the rubber trans gasket that came with the 1st kit started leaking after 3 weeks. so had to remove pan again and use the thin gasket that is oem for this car. i have noticed that I need to let vehicle run for about 7-10 minutes or it will not shift into 2nd or 3rd or 4th etc. but once warm shifts well (no flogging) and no odd sounds like i was getting when I 1st purchased it in march. (sounded like a bad wheel bearing) sad thing is my Bentley manual troubleshoots it as a worn drive shaft bearing. NOT!! the transmission on this model is basically a luxury car trans. designed to shift without causing passengers any discomfort. so it does the hunting thing at low speed as part of it's design. Sport mode is still an enigma to Me, not sure on where the shift points are in regards to RPM's mine shifts from 1st to 2nd at 2000 rpm and does not shift again until 3200 rpm is that normal. What is the deal with the manual/auto switch for the tranny? do I use that in conjunction with sport mode? love this cheap car paid 3000.00.. parts are cheap considering what it is. have a porsche 944 and a Jaguar XJS v12 parts are expensive. I dive My 740 like an old man so it should serve Me well.
 
#76 ·
fluid leak between tranny and engine GREEN

okay here's an odd one. My synthetic transmission oil is red. My engine oil is brown. yet I have a small green oil drip coming from just behind the flywheel on My '95 740il .... oil looks clean but I do not know what it is, it does not smell burnt. smells a bit like power steering or brake fluid but is not leaking from any fittings. IDEA'S?
 
#81 ·
okay here's an odd one. My synthetic transmission oil is red. My engine oil is brown. yet I have a small green oil drip coming from just behind the flywheel on My '95 740il .... oil looks clean but I do not know what it is, it does not smell burnt. smells a bit like power steering or brake fluid but is not leaking from any fittings. IDEA'S?
Condensed coolant additive. You probably have a leak from the valley pan gasket. If it was leaking from a hose, you generally only see a whitish crust on the hose itself.
 
#77 ·
filler tube mod

It's not worth considering a mod to add a filler tube to these transmissions. They are very sensitive to oil level. The level is set by the level plug up an indention/tube cast in the sump. When it overflows it's correct, but provided that the fluid is at the right temerature! Diagnostics can measure the temperature for you, but it's all a bit of a pain! Sadly, it really does matter.
 
#86 ·
It's not worth considering a mod to add a filler tube to these transmissions. They are very sensitive to oil level. The level is set by the level plug up an indention/tube cast in the sump. When it overflows it's correct, but provided that the fluid is at the right temerature! Diagnostics can measure the temperature for you, but it's all a bit of a pain! Sadly, it really does matter.
Since I don't enjoy crawling under the car a filler tube would be a nice option.

Isn't it interesting. For many decades we checked fluid levels using a dipstick. The dipsticks were marked indicating the level and whether or not to check it hot or cold. The owner's manuals had direction on what hot or cold meant.

Now we have "lifetime" units and all this mysticism woven around them. It is still a closed unit. It still uses a specific volume of lubricant. It is still checked at a given temperature. The fluid has a specific expansion coefficient. Just engineering stuff. No magic.
 
#78 ·
Tranny history

Just a note on how my problems were solved. Problem rpm variation at steady speed ( 100 - 200 rpm). Converter lockup.
Changed fluid and filter worked great for 2 years 85000 miles until 120000. Stored for winter problem came back. Added 4 oz of Dr. Tranny Shudder Fixx now smooth as new.

2000 740il
 
#80 ·
These discussions on "lifetime" transmission fluid pop up regularly, as does advice on not changing the fluid because it may dislodge sediment which will then cause the trans to fail.

"lifetime" is generally accepted to be 10 years or 100,000 miles. All transmissions wear over time, and all transmission fluid breaks down over time. The more aggressively the car is driven, and the greater the heat generated in the trans fluid, the faster this deterioration will occur. So some owners may see 200,000 miles on the original fluid, whilst others may have trans problems much earlier.

Best test is to check the colour of the trans fluid and check for the presence of fine metallic particles. Irrespective of mileage, if the fluid is clear and bright, chances are there is nothing to worry about; if it's dark and cloudy, time to change fluid and filter (only use Filtran filters). There is an argument for removing and cleaning out the valve body if you have particularly dirty fluid, as this will be the part which suffers from sediment which may be set free from the fluid change. Sticking or leaking valves leading to lower than required fluid pressure on the clutches, allowing clutch slippage, is generally what will cause transmission failure.
 
#83 ·
While driving my 2001 740il bmw down the road transmission failsafe mode came on my cluster and my car would only take off in 4 gear and all my gauges work sometimes I pulled over and shut it off and started it back up but it still stayed the same can anybody help me


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#85 ·
I had loads of problems with my autobox on my range rover. It was the zf5 hp (same as the e38. I kept on getting a grinding sound when driving on the motorway and it kept on holding gears and bumping when changing
. Ended up having the box recconed costing £2000, then it was still holding gears. Frustrated i looked on for answers. I got a laser thermometer and pointed it at the sump pan on the box. The fluid was clearly overheating. it was up at 122 degrees. So i changed the ATF radiator that links onto the cooling system. Apparently if you've got an old rad with sludge building up it clogs up the pipes for the ATF radiator, as it's fed off of the bottom of the cooling system radiator. This seemed to be a weak point of the setup, and definitely worth checking, especially to see the temperature as it has to really overheat to go into failsafe mode which is where you don't want to be. After changing the AFT cooler it solved all the initial problem, which would have been cooking the fluid and potentially damaging the box. Anyway, that was my experience. I maybe wrong, but aren't you supposed to always stick with the same fluid as previously used in these box's ie the same brand and specs so that you don't mix two different types together that produce some more problems?
 
#90 ·
My E38 has 89xxxk on it. From day one I've had TC lockup issues. All the symptoms (exactly) that have been described by others.

Terrified to change the tranny fluid due to the issues you've just had.

It is my only car and I commute 20 miles (one way) to work 6 days a week.

At this point I'm thinking about buying a second car "in case".

I didn't recognise it when I bought it, but the car has been abused and never taken care of. It needed work from the start. Intake manifold gaskets, replaced the ccv, csp, and a few other things minor. Still have not gotten the courage to take on the transmission issue.

I love the car, regret buying it as primary transportation.

Sent from my QMV7B using Tapatalk
 
#92 ·
See post #78.
 
#93 ·
I am back for more. After the last code and inspection afterward I found a bit more metal on the magnets but none in the valve body or screens of the solenoids.

The trans still growls a little when cold but not has over 202k on it and still going.

I just bought a 2000 X5 that has 89k on it. I am going to pull the pan and inspect that trans as well. I thought I my drain and inspect the 740 as well just for grins.

I fully expected to have a failed trans in the 740 by now but it is still going.

-Mike O
 
#95 ·
Here is the solution to the original bruce r post. Around 35 to 40 mph on light acceleration transmission controller starts applying the torque converter lock up clutch. It utilizes pusle width modulation and the electric solenoid that opens the valve inside the valve body. Hydraulic pressure slowly starts to apply the clutch and once the the clutch is applied fully pwm is at 99%. The reason for the noise from the torque converter is because the clutch disc is slipping and after a long time of driving with this condition the vlutch is wore out. The actual problem is inside the valve body.
The fix:
Please have in mind that this only applys to a worn TCC and noise coming from TC.
Dont waste your time with changing the filter and the fluid. Reprogramming and relearning will not work eighter.
Replace the torque converter with a new one 340s
Send the valve body to be rebuilt or purchase the rebuild valve body. I found mine on ebay and yes its expensive. 800S. The manual valve has been rattling inside the valve body and the oil pressure is lower than it should be. This means that the aluminum bore is wore out and the only fix is to rebore the vale body and install the new slightly bigger valve. Unfortunately i could not find the bore kit and ended up buying the new valve body.
Total cost 1600 S and I have done all of the work myself.
Transmission works like new.
Another solution is buying used 5hp24 from a salvage yard.
 
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