5EAT Ask your Questions!?!

might be a wheel bearing if it doesn't change when changing gears?

I have an 2008 LGT 5EAT. Not sure if its the 100% transmission or something else, but there's a weird noise when accelerating. I guess the best way to explain the noise is it sounds like a reverse noise, but not as long. The noise pitch increase as i accelerate and goes away when I'm at a steady speed or left off the gas. Noise pitch does not change when changing gears.

 

Any ideas what it can be?

 

Turbo ready to explode ?

 

If it is and you started your engine cold after this your engine is likely toast

Turbo ready to explode ?

 

If it is and you started your engine cold after this your engine is likely toast

 

That's what I was thinking too...

I guess the best way to explain the noise is it sounds like a reverse noise, but not as long. The noise pitch increase as i accelerate and goes away when I'm at a steady speed or left off the gas. Noise pitch does not change when changing gears.

 

Any ideas what it can be?

 

doubt its wheel bearing !

 

i suggest you don't start your car.. and get it towed ( with out starting it ) and have the turbo checked( with out starting it ).

 

if you start it after a turbo failure all the bits bypass the filter and go on all the precise machined parts and ruin them.

 

 

its very common for people to change the turbo and then the engine will fail a few days/ weeks later. ( and kill the turbo again )

Edited August 5, 2015 by frank_ster

wouldn't the pitch change with gear change if it was the turbo? The RPM would be changing so the flow over the turbo would change?

Not reay as the boost goes up as rpm goes down.

Basically the same flow 4000 rpm and up. and if the turbo is chewing its self to peices its likly reaching a terminal surface speed acting as a governor.

 

he also mentioned it goes away as he lets off the throttle.

Edited August 5, 2015 by frank_ster

doubt its wheel bearing !

 

i suggest you don't start your car.. and get it towed ( with out starting it ) and have the turbo checked( with out starting it ).

 

if you start it after a turbo failure all the bits bypass the filter and go on all the precise machined parts and ruin them.

 

 

its very common for people to change the turbo and then the engine will fail a few days/ weeks later. ( and kill the turbo again )

 

 

Thanks for the advice. I will get that looked at.

^ please update us, as it can help trouble shoot issues in the future.

I would suspect front or centre diff backlash / wear

 

Tends to make a "straight cut" sound like reverse as they wear out

 

Speaking of front diffs, (and this is aimed almost exclusive at frankster / climber d), my 3.27 final ratio is robbing me of acceleration. I have a post facelift (2009 onward for you usdm folk) entire trans and rear diff here that I am keen to try and swap in. This will give me a shorter final drive (3.53 from memory) to assist in acceleration.

 

Will my reduction drive ratio be thrown out? Will this work?

 

Mick

Im worried you will have tcu issues, not sure how the tcu will feel

About different ratios.

Mechanically it should work fine . As long as the rear and fromt diff is the same .

 

You could make your car think its manual. And then use aftermarket tcu such as megashift. I started a thread on it.

I would suspect front or centre diff backlash / wear

 

Tends to make a "straight cut" sound like reverse as they wear out

 

Mick

 

I think this might be it. I googled it and found a video of a bad diff. Sounds like the noise i'm hearing.

 

Will get that looked at.

 

Thanks!

The pitch will change with vehicle speed. And will go away when you let off the throttle. But come back as soon as you touch the throttle. And usually it's the same sound for 10% throttle as 100% throttle.

So it usually makes noise at steady speed.

Im worried you will have tcu issues, not sure how the tcu will feel

About different ratios.

Mechanically it should work fine . As long as the rear and fromt diff is the same .

 

You could make your car think its manual. And then use aftermarket tcu such as megashift. I started a thread on it.

 

I've also got the post facelift tcu (09 usdm onward). Do you know if plugs are the same? And if I installed it, will my ecu be able to communicate with this newer tcu?

 

From memory when I looked at this some time back, the wiring schematic was different between the two models.

 

What's the mega shift worth?

 

Mick

Just realized I made a fundamental mistake which makes this irrelevant now. Post facelift (09 usdm) 5eat had 3.08 final drive which is taller than my current. Not what I'm after

 

Back to drawing board

yea you need outback 05-08 gearing

I've also got the post facelift tcu (09 usdm onward). Do you know if plugs are the same? And if I installed it, will my ecu be able to communicate with this newer tcu?

 

From memory when I looked at this some time back, the wiring schematic was different between the two models.

 

What's the mega shift worth?

 

Mick

the older 5 eat and 08+ 5 eats have different control strategy and its not gonna work with older tcu.

yea you need outback 05-08 gearing

 

 

Damn I just sold one of these too

 

Thanks frank will search your mega shift thread

 

Mick

(Q to) Hello fellow 5EAT enthusiasts, Re: Requested Torque maps tuning for larger turbos on 5EAT.

 

I got a Borg Warner EFR 7163 - a 62lb/min turbo on my 06" OBXT.

My 5EAT transmission is custom made by HexMods to handle all this tq & hp

(I estimate over 500hp at the crank on e85.)

 

On e85 the transmission is performing like a champ (kudos HexMods!), not slipping,

no rough shifts, just bang, bang, Bang and I am well over 60mph in under 4 sec.

Many surprised M calls BMWs and big dumb V8 cars...

 

But, while all is fine on e85, on Cal 91 I keep getting TCU error codes which causes the

tranny to go into "safe" mode preventing TC lockup - heating as a results.

 

It consistently happens under low/middle throttle, typically when I am in cruse control @~70mph - when load is slightly increasing (like when the HW begins to climb slightly up a very small incline.).

It does NOT happen when under WOT or other high throttle applications.

Takes couple of days to erase/disappear making it difficult to plan long trips away

from e85.

 

Presently my "Requested Torque values" maps are OEM - which seems to work when using e85 (turbo spools up faster, more torque,) but generates TCU errors when, I suspect, the " Requested Torque value" cannot be reached when I run on Cal 91 octane - slower spool, shallower torque curve.

 

Can ppl offer an alternative interpretation or, confirm this line of reasoning...?

 

I am thinking of generating tuning maps(s) with altered Requested Torque values

to try to make the computers think that all is fine by, for example, requesting Less torque when running on 91.

 

Thanks in advance for any comments, suggestions, shared experiences will be much appreciated.

Edited August 10, 2015 by KGB

I had a Holset on my 2.5 and never had these problems. You could disconnect the waste gate one stock turbo car and it won't do what you are saying.

 

What are you changing when you go from e85 to 91 ?

 

It sounds like it's more to do with some other load calculations .

 

What are the differences between e85 tune and 91 in the tunes ?

How did you change the injector scaling ? I herd some people just remapped the maf instead of injector size . Both work on a 5mt car but not on a auto

(Q to) Hello fellow 5EAT enthusiasts, Re: Requested Torque maps tuning for larger turbos on 5EAT.

 

I got a Borg Warner EFR 7163 - a 62lb/min turbo on my 06" OBXT.

My 5EAT transmission is custom made by HexMods to handle all this tq & hp

(I estimate over 500hp at the crank on e85.)

 

On e85 the transmission is performing like a champ (kudos HexMods!), not slipping,

no rough shifts, just bang, bang, Bang and I am well over 60mph in under 4 sec.

Many surprised M calls BMWs and big dumb V8 cars...

 

But, while all is fine on e85, on Cal 91 I keep getting TCU error codes which causes the

tranny to go into "safe" mode preventing TC lockup - heating as a results.

 

It consistently happens under low/middle throttle, typically when I am in cruse control @~70mph - when load is slightly increasing (like when the HW begins to climb slightly up a very small incline.).

It does NOT happen when under WOT or other high throttle applications.

Takes couple of days to erase/disappear making it difficult to plan long trips away

from e85.

 

Presently my "Requested Torque values" maps are OEM - which seems to work when using e85 (turbo spools up faster, more torque,) but generates TCU errors when, I suspect, the " Requested Torque value" cannot be reached when I run on Cal 91 octane - slower spool, shallower torque curve.

 

Can ppl offer an alternative interpretation or, confirm this line of reasoning...?

 

I am thinking of generating tuning maps(s) with altered Requested Torque values

to try to make the computers think that all is fine by, for example, requesting Less torque when running on 91.

 

Thanks in advance for any comments, suggestions, shared experiences will be much appreciated.

 

In comparison to you car, I will be tuning a JDM version with GSC S1 cams and the EFR 7670 located here. http://xtremeracingtuning.com/forum/viewtopic.php?f=40&t=581

 

Car been delayed due to builder but similar mods like you so I will see. But we will be tuning the tranny to see how it works.

 

I have had great success in working with a 3R 5EAT tuned in the mountainous region of California. SO I will use the info gain to see how this 600+whp LGT will shift. F1 says no issue, but we will see.

 

I have had past experience for over a year now working witht he 5EAT, but the above car we did quite some work for shifting close to like manual, so as the customer states. Bur for the JDM, I might most probably fly down for actual testing. We would like to implement the Syvecs in it, but we dont know the TCU CANBUS coding and the car is down to do sniffing with ecuflash.

 

On another note your tuner NEEDS to tune the other TQ req to the tranny TCU. If I had your rom I would tell the locations in it. For JDM, there are multiple map that affects the transmission that we will test once the engine is broken in.

 

The table he needs to look for can represent (In EMS terms MBT Torque Estimate, Driver Demand Torque, EngTqReq, etc, etc) Calculated Engine Torque (Eng. Load vs RPM).

 

More reading can be done here, but not too much:- http://www.romraider.com/forum/viewtopic.php?f=3&t=11418&hilit=5eat&start=15

Edited August 11, 2015 by west_minist

frank_steer;

I am not familiar with Holset, what is it?

The diff between 91 and e85 are mostly in timing and fuel maps.

indeed it probably has something to do with the load calculations -

I'll be working with Paul at Yimi sport in LA this Friday to try to generate some alternative maps for 91.

 

We can either Increase "requested torque" or decrease it,

and its rate of change -

what would you recommend?

 

West_minist - looking forward to hearing your feedback on the 7670 - its a big turbo and can do damage to the tranny if not properly strengthened. F1 and Diff bushings will help but I think you'll eventually want more clutch plates (this is what I got.)

either way, I would suggest monitoring the temp In AND Out of the tranny - you'll want to know if its getting hot and when...

 

Cheers!

see if he played with the maf scaling. I would leave the requested torque alone.

 

The trans seems to use the maf for trans load calculations From what I can tell .

 

 

 

Holset hx35 w from Dodge Ram with Cummings , schools buses ,small semi's big ass turbo.

frank_steer;

West_minist - looking forward to hearing your feedback on the 7670 - its a big turbo and can do damage to the tranny if not properly strengthened. F1 and Diff bushings will help but I think you'll eventually want more clutch plates (this is what I got.)

either way, I would suggest monitoring the temp In AND Out of the tranny - you'll want to know if its getting hot and when...

 

Cheers!

 

Lol... theoretically not as big as yours

 

All done. The customer is familiar with his needs and really prepared for it. Most failing could be in the axles etc. We will see. Our problem is he want to keep the 5EAT and not want to go to the 4EAT, but if we tear down the 5EAT and use a computer to control it, but it is expensive and will take tranny knowledge to do so. Basically everything was kind off design around the EFR. I wanted 700whp!!! he wanted 500whp. SO we settle in between and design around that. That also includes a Fuel Cell setup and fuel delivery. Again it will be an interesting product but I know we want to shift to the Syvecs, but again for right now, its the 5EAT and its control.

 

Do you have any gear pulls you can share, even a driving log?

 

Break-in period soon start. I cannot wait. We will run waste-gate pressure and a pretty stock rom. Then will start to ramp it up slowly. We most likely will shift to a Tial WG and will rev to 8000-8500.But having a good rev range for a good VE to 7500-8000 would be great with the GSC 1 cams. There are so many unknowns, its enticing especially the tranny operation. The sweetest thing is that it is an auto, so the turbo spooling would be better and after performing testing in getting the 5EAT to shift quicker and easier, I thing we will be happy.

 

We started looking at a SAS antilag WRC like kit (http://brewedmotors.com/blog/turbo-antilag-als-tuning-rally-style-secondary-air-injection) for the car, but before that, we just want to run, set some times on both the drag and track and once he is happy, move into some other areas. Please message me so we can keep posted. I know he would want to see how you are doing, although you are 2.5l. The JDM is 2.0 with build heads for VE increases.

Edited August 12, 2015 by west_minist

^ stand alone tcu

 

i havent broken any axles, my rear diff took a dump and i broke 3 center diffs.

Well we had look at the company PCM for it. They dont support it and we will be on our own with the PCM TCM-2000. So the last option is just use the Syvecs to control it if we do decided to invest the time and money. I know we can get it done, but living in two different countries isn't easy. Maybe he ship's the car to me ....Next step is to work with a 5EAT or transmission specialist. I have a very basic understanding how an auto works, but it wouldn't take much I guess for someone to understand the in/outs. Maybe I can log all of its operations (never did look at it) to see how they come together and implement it with the Syvecs or some other powerful Powertrain Controller. Edited August 12, 2015 by west_minist