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BMW and MINI DIY Videos – How to Change Under Car Fluids

Sep 29 14

While all of us know the importance of regular engine oil changes – and the penalties of neglecting this common maintenance task – there are at least two, and up to four, other important fluid changes that we tend to ignore. Perhaps the most neglected maintenance tasks on many vehicles, including our BMWs and MINIs, are the regular changing of the fluids in the under-car gearbox assemblies.  This includes the transmission (trans-axle on MINIs), rear differential (all current BMWs and 4wd MINIs), transfer-case (4wd models) and front differential (4wd models).

Like engine oil, the fluids in your BMWs or MINI’s transmission, differential(s) and transfer case perform two elemental tasks. They not only lubricate and prevent wear to the parts that are moving against each other, they also help cool the assembly by removing heat from the metal parts and transferring it to the case. Air moving over the outside of the iron or aluminum case then removes the heat from the case. Unlike engine oil, these fluids do not build up contamination from engine combustion byproducts.  They do, however, break down from heat and “shear” (the fluid’s molecules being broken down by the grinding action of the gears and bearings). Additionally, these fluids do become contaminated with minute metallic particles that are the byproducts of metal-on-metal wear.

The best way to assure that your BMW’s or MINI’s differential, transmission and transfer-case oils are doing their jobs (anti-wear & cooling), and protecting their respective assemblies, is to replace them regularly. We recommend following the BavAuto Ultimate Maintenance Schedule for your specific BMW or MINI model (www.blog.bavauto.com/go/maintenance). This is a relatively simple task.  If you are already changing your own engine oil, you should be able to change your other “under-car fluids”.

In this series of DIY videos, we will be showing examples of the various under-car fluid changes for the transmission, front and rear differentials and the transfer-case.  These videos will guide you in the basic procedures and the tools needed, for changing these fluids.  Your specific model BMW or MINI may differ in drain and fill plug locations.  The applicable Bentley publishing repair manual will cover details of fluid-type and drain and fill plug locations for the various BMW and MINI models.  The fill and drain plugs can be of four basic types, depending on the model and year; 1) external hex (commonly 10mm, 14mm or 17mm), 2) internal hex (Allen-type; commonly 10mm, 14mm or 17mm), 3) Torx (external-head; various sizes), 4) E-Torx (internal-head, various sizes).

Common tools needed for under-car fluid changes include a floor jack, jack-stands (in some cases drive-on ramps can be used), common mechanic’s metric tools and the various special tools and fluids detailed in each of the individual DIY videos below.  All are available in our online store at www.bavauto.com or by calling our Advisors at 800-535-2002.


Engine oil:

In a prior DIY video, we have covered a common BMW or MINI engine oil change, using the BavAuto Vacuum Oil changer.  This tool allows us to vacuum (suck) the oil from the engine’s oil pan, via the dip-stick tube (see DIY video link below).  However, this tool will not work for models that do not have an engine oil dip-stick.  These models must have the oil drained from under the car (as can be done on any BMW or MINI model, regardless of whether it has a dip-stick or not).  The refill procedures on these models are a bit unique due to the lack of a dip-stick.  We’ll cover the under-car oil drain (to be applied to any model), as well as the unique procedures for re-filling on the models without dip-sticks, in this DIY video.

Click HERE to watch the Under Car Oil Change Diy Video.


Automatic Transmissions:

We’ve covered the fluid and filter changes in previous Fast Times issues and DIY videos. Check out the Fast Times newsletter articles, Tech-blog posts and DIY videos noted below.

For a photo DIY, done on a 2000 540i, check the Spring 2006 issue of Fast Times at:
Spring 2006 Fast Times Newsletter – BMW Automatic Transmission Fluid and Filter Change DIY

View the DIY videos at:
Typical BMW Automatic Transmission Fluid and Filter Change DIY Video
and
BMW ZF 6HP Automatic Transmission Fluid and Filter Change DIY Video


Manual Transmissions
:

On a manual transmission case, there are both a fill plug and a drain plug. The fill plug is normally on the passenger side of the transmission case, near the middle of the side of the case. The drain plug is on the bottom of the transmission, typically at the rear or middle of the case.

Most manual transmissions will need 1.5 to 2 quarts, or liters, for a fluid change.  Check the applicable Bentley repair manual for model specific fluid quantities.

Click HERE to watch the Manual Transmission Fluid Change DIY Video.


Rear Differentials:

Similar to the manual transmission, the differential will have a drain and a fill plug.  The plugs are commonly in the rear cover of the differential, but note that some models have one or both plugs in the side of the main housing. Additionally, some late models only have a fill plug (there is no drain plug on the assembly).  These models require a unique procedure in order to evacuate the fluid.  We will address this is the DIY video.

Most rear differentials will need just over 1 quart, or liter, for a fluid change.  Some models do require more than 2 quarts (liters).  Check the applicable Bentley repair manual for specific fluid quantities.

Click HERE to watch the Rear Differential Fluid Change DIY Video.


Front Differentials:

Front differentials are very similar to rear differentials, but hold very little fluid, comparatively.  This makes if very important to keep fresh fluid in these assemblies.  We would even suggest that you change this fluid more often that even the BavAuto Ultimate maintenance Schedule suggests.  In most cases, less than one quart (liter) of fluid is needed for a fluid change   However, you should check the Bentley repair manual before purchasing fluid to be sure that you have the proper amount.

Click HERE to watch the Front Differential Fluid Change DIY Video.


Transfer-Cases:

The transfer-case, for four wheel drive models, is similar to the manual transmissions and differentials.  It typically has a fill and a drain plug.  As with the rear differentials, some models only have a fill plug and require special steps for fluid evacuation, which will be shown in the DIY video.

Like the front differentials, most transfer cases contain very little fluid and frequent fluid changes are recommended.  The specific fluid quantities are noted in the model specific Bentley repair manuals.

Click HERE to watch the 4wd Transfer Case Fluid Change DIY Video.


Trans-axles (MINI):

Being front wheel drive, MINIs use a combination transmission and front differential assembly, known as a trans-axle.  The four wheel drive minis use a trans-axle as well, plus a transfer-case.  Since the transmission and the front differential are incorporated into the same case, the fluid is also common to both parts of the trans-axle assembly.  Therefore, the transaxle fluids are unique.  This also means that fresh fluid is very important, as the two systems within the trans-axle assembly are working the fluid heavily.

Fluid changes for  the manual transmission trans-axles is very similar to that for a standard BMW rear wheel drive manual transmission, with drain and fill plugs.  While the general procedures for the automatic transmission models is similar to a BMW application, we must note that the fluid pan cannot be readily removed, as the engine and suspension lower cross-member is directly under the pan.  The cross-member must be lowered slightly in order to remove the fluid pan and access the filter.

As with the other BMW and MINI fluid changes, consult the Bentley repair manual for fluid capacities.

Click HERE to watch the MINI Manual Trans-Axle Fluid Change DIY Video.

 

BMW and MINI DIY Video – How to Change 4wd Transfer Case Fluid – Undercar Fluid Changes

Sep 29 14

While all of us know the importance of regular engine oil changes – and the penalties of neglecting this common maintenance task – there are at least two, and up to four, other important fluid changes that we tend to ignore. Perhaps the most neglected maintenance tasks on many vehicles, including our BMWs and MINIs, are the regular changing of the fluids in the under-car gearbox assemblies.  This includes the transmission (trans-axle on MINIs), rear differential (all current BMWs and 4wd MINIs), transfer-case (4wd models) and front differential (4wd models).

This DIY (Do It Yourself) How-To video shows how to change the fluid in a typical 4WD BMW or MINI transfer case.  See our other “Under Car Fluid Changes” videos for; front differential, manual transmission, automatic transmission, rear differential, MINI transaxle and standard under-car oil change.

The transfer-case, for four wheel drive models, is similar to the manual transmissions and differentials.  It typically has a fill and a drain plug.  As with the rear differentials, some models only have a fill plug and require special steps for fluid evacuation, which is shown in the DIY video for changing the REAR differential fluid.

Like the front differentials, most transfer cases contain very little fluid and frequent fluid changes are recommended.  The specific fluid quantities are noted in the model specific Bentley repair manuals.

NOTE:
We are performing these fluid changes on a vehicle lift.  All of these fluid changes cane be done “at home” using a common floor jack and jack stands or even drive-on ramps).

Parts & Tools:

Common tools needed for under-car fluid changes include a floor jack, jack-stands (in some cases drive-on ramps can be used), common mechanic’s metric tools.  Below is a listing of the specialty tools and parts/fluids for performing the rear differential fluid change.  All are available in our online store at www.bavauto.com or by calling our Advisors at 800-535-2002.

* Red Line and Liqui-Moly Early Transfer Case Fluids (click image):

* BMW and MINI Late-Model Transfer Case Fluid (click image):

* Under Car Fluid Drain & Catch Pan (click image):

* 1/2 Liter Fluid Transfer Pump (click image):

* 1.5 Liter Fluid Transfer Pump (click image):

* Power-Fill Fluid Transfer Tool (click image):

* Vacuum Fluid Removal Pump (click image):

* Fluid Removal tool for “No Drain Plug” (click image):

* Drain Plug Wrench (14mm Allen & 17MM Box) (click image):

* Drain Plug Short Allen Bit Set (10mm, 14mm, 17mm) (click image):

* Magnetic Drain Plug (click image):

—-
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“Follow” us on Twitter – http://www.twitter.com/BavAuto
“Subscribe” to us on YouTube – http://www.youtube.com/BavarianAuto
Visit our online store – http://www.bavauto.com/
——–
All products noted in this video can be purchased in our online store, http://www.bavauto.com/, 24 hours a day, 7 days a week. You are also welcome to e-mail us at info@bavauto.com or call into our headquarters and speak to our knowledgeable Advisors at (800) 535-2002 (Mon.-Thurs. 8AM to 9PM EST, Fri. 8AM to 7PM EST, and Sat. 9AM to 4PM EST

BavAuto
www.BavAuto.com
Bavarian Autosport

BMW DIY Video – How to Change 4wd Front Differential Fluid – Undercar Fluid Changes

Sep 29 14

While all of us know the importance of regular engine oil changes – and the penalties of neglecting this common maintenance task – there are at least two, and up to four, other important fluid changes that we tend to ignore. Perhaps the most neglected maintenance tasks on many vehicles, including our BMWs and MINIs, are the regular changing of the fluids in the under-car gearbox assemblies.  This includes the transmission (trans-axle on MINIs), rear differential (all current BMWs and 4wd MINIs), transfer-case (4wd models) and front differential (4wd models).

This DIY (Do It Yourself) How-To video shows how to change the fluid in a typical BMW 4wd front differential.  See our other “Under Car Fluid Changes” videos for; rear differential, manual transmission, automatic transmission, transfer case, MINI transaxle and standard under-car oil change.

Similar to the manual transmission, the differential will have a drain and a fill plug.  Some late models only have a fill plug (there is no drain plug on the assembly).  These models require a unique procedure in order to evacuate the fluid.  We will address this is the DIY video for changing the REAR differential fluid.

Most front differentials will need just under 1 quart, or liter, for a fluid change.  Check the applicable Bentley repair manual for specific fluid quantities.

NOTE:
We are performing these fluid changes on a vehicle lift.  All of these fluid changes cane be done “at home” using a common floor jack and jack stands or even drive-on ramps).

Parts & Tools:

Common tools needed for under-car fluid changes include a floor jack, jack-stands (in some cases drive-on ramps can be used), common mechanic’s metric tools.  Below is a listing of the specialty tools and parts/fluids for performing the rear differential fluid change.  All are available in our online store at www.bavauto.com or by calling our Advisors at 800-535-2002.

* Red Line and Liqui-Moly Differential Fluids (click image):

* Under Car Fluid Drain & Catch Pan (click image):

* 1/2 Liter Fluid Transfer Pump (click image):

* 1.5 Liter Fluid Transfer Pump (click image):

* Power-Fill Fluid Transfer Tool (click image):

* Vacuum Fluid Removal Pump (click link):

* Fluid Removal tool for “No Drain Plug” (click link):

* Drain Plug Wrench (14mm Allen & 17MM Box) (click link):

* Drain Plug Short Allen Bit Set (10mm, 14mm, 17mm) (click image):

* Magnetic Drain Plug (click image):

—-
“Like” us on Facebook – http://www.facebook.com/BavarianAutosport
“Follow” us on Twitter – http://www.twitter.com/BavAuto
“Subscribe” to us on YouTube – http://www.youtube.com/BavarianAuto
Visit our online store – http://www.bavauto.com/
——–
All products noted in this video can be purchased in our online store, http://www.bavauto.com/, 24 hours a day, 7 days a week. You are also welcome to e-mail us at info@bavauto.com or call into our headquarters and speak to our knowledgeable Advisors at (800) 535-2002 (Mon.-Thurs. 8AM to 9PM EST, Fri. 8AM to 7PM EST, and Sat. 9AM to 4PM EST

BavAuto
www.BavAuto.com
Bavarian Autosport