Author Topic: Gear ratios  (Read 2683 times)

October 25, 2008, 12:09:07 pm

molgrips

  • Junior

  • Offline
  • **

  • 134
Gear ratios
« on: October 25, 2008, 12:09:07 pm »
So I've searched the site and I've found that there are loads of transmissions and people are talking about changing individual gears or the final drive ratios...

The question is, what's the easiest way of making my gears longer on my 1994 Passat 1.9 TD?  I'm running at about 2900rpm at 70mph, which is kinda noisy.  The engine gets noisy at 2,500rpm, and there's also something resonating which makes it worse.

So it's either:

a) Get bigger wheels - I've got 14s on it now.  Can you recalibrate the speedo?
b) Replace the tranny with one from a scrap yard - only these seem to be hard to find these days
c) Replace 5th
d) Change the final drive

I'd prefer option d), but I don't know if it's possible.

Which is easiest?  I've never worked on a transmission before :)
1994 Passat 1.9 TD Estate, 180k miles, running on veg oil

Reply #1October 25, 2008, 01:10:34 pm

Dirtrag2

  • Veteran

  • Offline
  • ***

  • 298
Gear ratios
« Reply #1 on: October 25, 2008, 01:10:34 pm »
I think replacing 5th is the easiest... check out this link for the DYI http://www.brokevw.com/
...Darcy
'97 Jetta 1.9TD ( dirtrag2 )
'88 Fox Wagon ( projekt Dirtrag 3 )

Reply #2October 25, 2008, 01:17:42 pm

jtanguay

  • Veteran

  • Offline
  • ***

  • 6879
Gear ratios
« Reply #2 on: October 25, 2008, 01:17:42 pm »
put bigger tires, grab a tranny with a taller r&p and then install the .655 5th gear.  you'll be cruising 80mph @ 2500 rpm  8) but need to downshift for hills  :lol:

but yea apparently its pretty easy to replace 5th gear on these trannies.  and can be done in car!  also a good time to replace the oil.  bleached bora sells the 5th gear sets. forget his site url though.


This is how we deal with porn spammers! You've been warned.

Reply #3October 26, 2008, 01:40:09 am

molgrips

  • Junior

  • Offline
  • **

  • 134
Gear ratios
« Reply #3 on: October 26, 2008, 01:40:09 am »
Erk, doens't look all that easy.. but I guess it's always better when you get things out and can see them....
1994 Passat 1.9 TD Estate, 180k miles, running on veg oil

Reply #4October 26, 2008, 03:24:38 am

Turbinepowered

  • Veteran

  • Offline
  • ***

  • 1206
Gear ratios
« Reply #4 on: October 26, 2008, 03:24:38 am »
Quote from: "jtanguay"
put bigger tires, grab a tranny with a taller r&p and then install the .655 5th gear.  you'll be cruising 80mph @ 2500 rpm  8) but need to downshift for hills  :lol:

but yea apparently its pretty easy to replace 5th gear on these trannies.  and can be done in car!  also a good time to replace the oil.  bleached bora sells the 5th gear sets. forget his site url though.


www.boraparts.com is his linked-to site, but a quick glance through didn't turn up any transmission parts like that. Granted, might be like Myke and not have everything he has in his stock listed on his site.

Reply #5October 26, 2008, 10:26:44 am

cyrus #1

  • Veteran

  • Offline
  • ***

  • 360
Gear ratios
« Reply #5 on: October 26, 2008, 10:26:44 am »
http://www.boraparts.com/catalog/advanced_search_result.php?keywords=5th&x=61&y=6&categories_id=&inc_subcat=1&manufacturers_id=&pfrom=&pto=&dfrom=&dto=

Here's a .681 and a .658 5th.  If you're looking for ease of install, I would stay away from R&P swaps.  Excuse my ignorance but would this passat have an O2O or an O2A?
Cody

2002 Jetta TDI
2000 Jetta TDI - R.I.P.
1990 Jetta 8v-Eventually to be 1.6TD

Reply #6October 26, 2008, 11:26:02 am

molgrips

  • Junior

  • Offline
  • **

  • 134
Gear ratios
« Reply #6 on: October 26, 2008, 11:26:02 am »
$350!  That's a bit more than I thought for a couple of cogs...!

If that's how much it costs, maybe I'll just get bigger wheels...
1994 Passat 1.9 TD Estate, 180k miles, running on veg oil

Reply #7October 26, 2008, 11:27:04 am

molgrips

  • Junior

  • Offline
  • **

  • 134
Gear ratios
« Reply #7 on: October 26, 2008, 11:27:04 am »
PS what's R&P mean?
1994 Passat 1.9 TD Estate, 180k miles, running on veg oil

Reply #8October 26, 2008, 11:31:45 am

cyrus #1

  • Veteran

  • Offline
  • ***

  • 360
Gear ratios
« Reply #8 on: October 26, 2008, 11:31:45 am »
Ring & Pinion.  It's the final drive and to replace it you definitely need to crack open the trans.
Cody

2002 Jetta TDI
2000 Jetta TDI - R.I.P.
1990 Jetta 8v-Eventually to be 1.6TD

Reply #9October 26, 2008, 11:48:35 am

Jettagli16v

  • Veteran

  • Offline
  • ***

  • 344
Gear ratios
« Reply #9 on: October 26, 2008, 11:48:35 am »
R&P = Ring & Pinion (AKA Final drive) the ratio with which the output shaft turns the differential (consequently the tires)

Holy cow!
I did not even know I could get a .655,
I thought I was relegated to .75 & .71, and was looking for the 3.667 Final (ACL Trans code)

Now I have a new, elusive, abstract transmission part to seek out!
Currently: 81 Caddy 1.9 AAZ, 1995 Audi S6, 78 ASI/Riviera camper bus 2.0, 74 THING 1.8 (resto, coming in 2020).

Reply #10October 27, 2008, 02:57:17 pm

ericgoum

  • User+

  • Offline
  • *

  • 20
Gear ratios
« Reply #10 on: October 27, 2008, 02:57:17 pm »
If you go to the website http://a2resource.com/ you can see the gear ratios of all engines and can use it to figure out what you need at a junkyard. I currently have a .75 5th in my '85 Jetta and when I was at the junkyard recently found a vehicle that had a .71. Cost me 6$ for the gears and all parts relating to those gears. Should be good for a couple hundred RPM drop at the speeds you are talking. Maybe not as extreme as the others. I plan on replacing this sometime in the near future. Hope this helps.

Eric