How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Matt Your Own Question

Matt
Matt, Mechanical Engineer
Category: BMW
Satisfied Customers: 21117
Experience:  BEng hons Mech engineering, in auto industry 22 years
12772297
Type Your BMW Question Here...
Matt is online now

HiI have a 2006 E53 3.0d, the rear diff has destroyed

Customer Question

Hi I have a 2006 E53 3.0d, the rear diff has destroyed itself, the problem is locating another 3.91 ratio diff. My question is.....is it ok to change both the front and rear diff to a different ratio; say 3.64 which are both available? they are from a 2003 model, as far as I can see the only difference is the drive shaft flange which I can remove and replace with the one from my broken diff.

Submitted: 2 years ago.
Category: BMW
Expert:  Shantal-Mod replied 2 years ago.
Hello,
I'm Shantal and I'm a moderator for this topic.
I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.
I was checking to see if you had already found your answer or if you still need assistance from one of the Professionals.
Please let me know if you wish to continue waiting or if you would like for us to close your question?
Thank you,
Shantal
Expert:  Matt replied 2 years ago.
Hello

providing you can get a dealer to update the software to recognise the new diff ratio then yes you can fit the taller ratio
the software needs updating so the speedo reads correctly

bear in mind its a reasonable step up in gearing so expect the acceleration to suffer but fuel consumption should improve on a long motorway run
Matt, Mechanical Engineer
Category: BMW
Satisfied Customers: 21117
Experience: BEng hons Mech engineering, in auto industry 22 years
Matt and other BMW Specialists are ready to help you
Customer: replied 2 years ago.
Hi Matt
Thanks for that, someone told me that it would destroy the transfer box.
Personally I don't see how, what is your view before I proceed to change the ratios
Expert:  Matt replied 2 years ago.
Hello

providing you match the front and rear ratios the transfer box will be fine
as you're not putting more torque through it as the engine is the same as before

the engine will be working harder on acceleration as the ratio is higher but the amount of torque transmitted into the transfer box is the same as before

What Customers are Saying:

 
 
 
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
< Previous | Next >
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C.
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex
 
 
 

Meet The Experts:

 
 
 
  • Matt

    Matt

    Mechanical Engineer

    Satisfied Customers:

    91
    BEng hons Mech engineering, in auto industry 22 years
< Previous | Next >
  • http://ww2.justanswer.com/uploads/35/350matt/2012-6-7_182356_matsavatr.64x64.jpg Matt's Avatar

    Matt

    Mechanical Engineer

    Satisfied Customers:

    91
    BEng hons Mech engineering, in auto industry 22 years
  • http://ww2.justanswer.com/uploads/Guest/2008-02-15_191551_avatar.jpg Roger's Avatar

    Roger

    BMW Master Tech

    Satisfied Customers:

    2823
    10 yrs. experience as BMW Master Technician, shop foreman and dealer.
  • http://ww2.justanswer.com/uploads/FO/fordtwo/2014-12-19_163422_arrepair.64x64.jpg Robert's Avatar

    Robert

    BMW Technician

    Satisfied Customers:

    82
    Fully qualified 19+yrs exp/self employed technician in the UK
  • http://ww2.justanswer.com/uploads/IN/indytech/2013-8-8_102717_SantoDomingo146598x6402.64x64.jpg Greg's Avatar

    Greg

    Technician

    Satisfied Customers:

    1087
    Automotive diagnostic tech
  • http://ww2.justanswer.com/uploads/TE/techmachine/0601821347169_717372168_8940977_39623330_o.64x64.jpg Ross's Avatar

    Ross

    Diagnostic and repair technician

    Satisfied Customers:

    467
    Licensed diagnostic and repair technician
  • http://ww2.justanswer.com/uploads/RO/RobMechanic/068.64x64.JPG Rob's Avatar

    Rob

    ASE Certified Technician

    Satisfied Customers:

    82
    30 years trade experience