All gears work fine, but will not shift into overdrive?

[Crowz]

Originally Posted by Fifty150hs

I'm not sure if you have a 5 speed or a 6 speed. In either case they don't have an "overdrive" per se. 5th and 6th are overdrive gears. You won't see any kind of "overdrive" indication. It will just be in the highest gear. Our transmissions use converter lock up. As adrewwynn noted you can see when the converter locks up and if it is properly locked up. In my 3.0 with a 5 speed, when I run the car up to 80 mph, initially it will be showing about 3200 rpm. When the converter locks up it drops to 2950. Small changes in speed when locked up will show small changes in rpm's.

The 5 speed automatics have an overdrive ratio for 5th gear.

The manual 5 speeds are 1:1 in 5th so no overdrive ratio. The 6 speed manuals have an overdrive ratio for 6th gear.

Later models like my e70 with the 8 speed have a VERY tall overdrive for the final gears. It was quite strange going from nearly 3000 rpms at 70 on the e53 to 1600 rpms in the e70. Its 1100 or 1200 rpm at 55mph in the e70.

[wpoll]

Originally Posted by Crowz

... Later models like my e70 with the 8 speed have a VERY tall overdrive for the final gears. It was quite strange going from nearly 3000 rpms at 70 on the e53 to 1600 rpms in the e70. Its 1100 or 1200 rpm at 55mph in the e70.

You can't really compare diesel rpms with petrol rpms in this way though - peak torque is at VERY different revs in a diesel so the gear ratios are VERY different. :-)

I suspect an e70 V8 would be closer in revs to the e53 petrol (6pd vs 8sp aside).

My e53 diesel runs about 2000rpm at 60mph. Clearly the 8sp tranny drops this a LOT. It may not even engage 8th gear at that speed...

*edit* Hang on - is your e70 the xDrive35i ? - in which case it's petrol - ignore me..

[Crowz]

Originally Posted by wpoll

You can't really compare diesel rpms with petrol rpms in this way though - peak torque is at VERY different revs in a diesel so the gear ratios are VERY different. :-)

I suspect an e70 V8 would be closer in revs to the e53 petrol (6pd vs 8sp aside).

My e53 diesel runs about 2000rpm at 60mph. Clearly the 8sp tranny drops this a LOT. It may not even engage 8th gear at that speed...

*edit* Hang on - is your e70 the xDrive35i ? - in which case it's petrol - ignore me..

Mine isn't a diesel its a gasser. Its the xdrive35i. Fast as all get out and geared waaaay low when cruising. Feels more like a big block old school v8 to be honest. Surprised me big time. Lot of torque.

[wpoll]

Originally Posted by Crowz

Mine isn't a diesel its a gasser. Its the xdrive35i. Fast as all get out and geared waaaay low when cruising. Feels more like a big block old school v8 to be honest. Surprised me big time. Lot of torque.

Yeah - silly me - just figured that out.. Crazy low revs for a gasser though... 1100-1200rpm at 55mph... It must have bugger all pick-up from that? I guess the turbo has "aggressive" geometry...

[Crowz]

Originally Posted by wpoll

Yeah - silly me - just figured that out.. Crazy low revs for a gasser though... 1100-1200rpm at 55mph... It must have bugger all pick-up from that? I guess the turbo has "aggressive" geometry...

I have driven probably 100 or more turbo vehicles in my life and this one is so weird the way it drives I always forget it even has a turbo. Its silent and has power all over the place. Usually theres whine as you get the revs up and they are a dog down low rpm wise. This thing has no noticeable turbo lag that I can find and has power from 1100 rpm on up. It gets even stronger the high the rev band but it feels very linear. Very non turbo feeling.

It also will get away from you fast if you aren't careful since you don't expect it to go nuts when floored as smooth as the power comes on driving normally.

If you ever get a chance to play with one I highly recommend it

I want to drive a Z4 with one in it one day. As stout as it is in my X5 it has got to be a wild ride in a Z4.

[wpoll]

Originally Posted by Crowz

I have driven probably 100 or more turbo vehicles in my life and this one is so weird the way it drives I always forget it even has a turbo. Its silent and has power all over the place. Usually theres whine as you get the revs up and they are a dog down low rpm wise. This thing has no noticeable turbo lag that I can find and has power from 1100 rpm on up. It gets even stronger the high the rev band but it feels very linear. Very non turbo feeling.

...

That'll be the twin-scroll turbo. Kinda like a VGT but it sounds like it's even more linear. Add in Valvetronic and you have an engine that produces it peak torque from 1200-4000rpm and peak power from 4000-6000rpm.

I bet 4000rpm is an exciting place to be!

[Crowz]

Originally Posted by wpoll

That'll be the twin-scroll turbo. Kinda like a VGT but it sounds like it's even more linear. Add in Valvetronic and you have an engine that produces it peak torque from 1200-4000rpm and peak power from 4000-6000rpm.

I bet 4000rpm is an exciting place to be!

Definitely perky up there.

Another thing I found weird was the mpg. It gets 25 to 26 mpg pretty easy on the interstate doing 70 plug mph.

21 mpg around town too.

[andrewwynn]

So on my NT-510 I can pull up real-time view of the Tc lock up. I wasn't driving at the time so of course it shows not locked.

One of my previous cars (99 sable) had a bug where the lock up solinoid was intermittent. I would lose a mpg at freeway speeds and get an occasional code.

The normal procedure to fix the sable was : step one remove transmission from the car, step two unscrew the $30 part and screw in the replacement. Step three return transmission to the car.

Needless to say I just lived with the occasional CEL on long trips.

Had I kept the car I was planning to drill a hole through the transmission hump to gain access to the solinoid!

I would look into if the transmission you have works similarly to engage the lock up. There are like 4 solinoids inside my X5 transmission. If I have the scanner connected next time I'm on a highway I'll see if one of them is in sync with TC lock.

I recommend the foxwell nt510/520 for DIY on the E53. There is another re-attach branded version it's identical but I don't know for sure if you can add more modules.

[Crowz]

Originally Posted by andrewwynn

So on my NT-510 I can pull up real-time view of the Tc lock up. I wasn't driving at the time so of course it shows not locked.

One of my previous cars (99 sable) had a bug where the lock up solinoid was intermittent. I would lose a mpg at freeway speeds and get an occasional code.

The normal procedure to fix the sable was : step one remove transmission from the car, step two unscrew the $30 part and screw in the replacement. Step three return transmission to the car.

Needless to say I just lived with the occasional CEL on long trips.

Had I kept the car I was planning to drill a hole through the transmission hump to gain access to the solinoid!

I would look into if the transmission you have works similarly to engage the lock up. There are like 4 solinoids inside my X5 transmission. If I have the scanner connected next time I'm on a highway I'll see if one of them is in sync with TC lock.

I recommend the foxwell nt510/520 for DIY on the E53. There is another re-attach branded version it's identical but I don't know for sure if you can add more modules.

I have that same foxwell scanner and while its a "good" tool that sucker is sooooo slow.

Its handy to have with you but I prefer using a notebook computer if I can.

[andrewwynn]

Painfully slow!

It gets much better when you skip the auto scan and just go in to the module needed. Eg tonight I needed to get real-time data on the gear shift position.



It took about a minute to scan the VIN and give me the list of modules. 30 seconds to get into the transmission module and 30 more seconds to check off the real-time options and display.

A full scan of all modules I like to start it then go get a drink and come back.