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Discussion Starter · #1 ·
5th Gear Swap QUESTIONS - MK5 Jetta TD


I am looking to modify my GQQ (manual 2006 Jetta TDI) transmission's 5th gear with either a .681 or .658 gear.

From my understanding the .681 is the perfect medium for modifications; thus it is my first choice. However, since I am doing extensive highway driving, a .658 gear would be more beneficial.

My questions are as follows:

-Does the modification to .681 or .658 prevent cruise control from working?
-What exactly requires modification to the spring plate for the .658 gear? And Why?
-Does the difference in RPM, 11% and 13%, .681 and .658 respectively, produce exceptional fuel savings?
-What should I expect to see in MPG gains from the .681 and .658 swaps?
-What is the best type of method to remove the gears; either remove transmission entirely or remove front drivers wheel and pull gears off while transmission is attached?
-What is the life expectancy of these modification?
-How much labor is involved, and would a dealership complete this job?
-What is a trustworthy dealer to purchase these modification kits?
-How much overall cost would this modification require?

I know there are a lot of questions, but I did my best research in an attempt to answer these questions. Therefore, I wouldn't be inquiring about all of this if I had found it.

If anyone could answer these for me that would be much appreciated.

Thank you everyone for all of your threads and posts; I am a much more informed VW owner now from your contribution.


(owner of 2006 Jetta SE TDI - approx. 120,000 km)

(main source: http://www.myturbodiesel.com/1000q/multi/5th-gear-swap-VW.htm)

Premium Member
23,902 Posts
On your car it shouldn't. But I've never tried it, this is based off what I've heard.
Don't know, try contacting the vendor.
Fuel savings are minimal depending on driving style. Some have reported no change, some have reported a few mpg.

I wouldn't remove the entire transmission, just remove cover.
life expectancy is life of transmission. IT doesn't shorten or stress anything else.
Dealership should have no problem but they don't normally do this sort of thing. Personally, I would do it myself because I don't trust dealer techs I don't know but that's just me.

For more on gearing changes, use this calculator. Those generic numbers are for a mk4, your mk5 has taller gearing.
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