[grizzly]

I was thinking about swapping the 5th gear with .681, I doubt I will make the money back in fuel, but is there any noticeable difference?

 

[chittychittybangbang]

I don't think you will save enough fuel to notice it. In other words, maybe 2-3 mpg highway. Definitely not more than 5 mpg, and you won't lose mileage ,everything else being equal. Load increases but rpm goes down. One increases fuel consumption and the other decreases fuel consumption. I think that you will save fuel, but it's well within tank-tank and seasonal variance in mpg so it's not very noticable. I don't drive any faster but the car is at 2000 or 2100 rpm instead of 2500 rpm and it's a lot quieter.

Here is the how-to: http://www.myturbodiesel.com/1000q_how_to/multi/5th_gear_swap.htm

If you do a lot of highway driving, it makes more sense, if you want to lower the highway rpm, have a chip or other power upgrade, if you plan on keeping the car long term, it makes more sense.

And remember that you can sell the old gear for about $100-150 to a gas VW 5 speed trans so the final cost is under $200.

 

[grizzly]

I think I will do it. Looks like an easy job, any common problems that people run into?

 

[jon applespeed]

The big locking washer on the gears is one way, make sure you put it on the right way, you can see in the writeup's pictures what I am talking about.

Make sure you keep everything clean. The writeup suggests using OEM transmission gear oil but I like Royal Purple gear oils. Make sure it's Gl4.

 

[darren]

The mileage difference is so small that I doubt you will save more fuel than it's worth. I don't have it but from what I hear it lowers the rpm. The car is quieter and since most people drive on the highway at 65 mph and faster, the swap might be for them.