Jump to content

1.4TDI 5th Gear Mod


Recommended Posts

Hi all, new to the forum :wave:

Just wondering if anyone has carried out the 5th gear modification on their 1.4TDI - basically it involves swapping out the existing 5th gear for a longer gear to reduce the revs which makes for quiter and more economical cruising.

Drivers of the 1.4TDI engined models will know that the standard 5th gear is rather short so when cruising at 70mph (or overtaking at higher speeds!) the engine doesn't feel very relaxed revving at 2600rpm+

If anyone has carried out this modification I would be very interested in hearing how it's worked out. Apparently, the idea is to make the 5th gear longer but not to make the gap between 4th-5th too long so that you have to keep downshifitng to 4th which would probably make the economy worse.

Cheers

Link to post
Share on other sites
  • 4 weeks later...

It's the faffing about pulling it all to bits ain't it, sure a second hand box wouldn't be that pricey.

as Jon says that's one point 2 it's a direct fit so if you gearbox is being refurbed bung it on then otherwise it can be done whilst on the car.

Link to post
Share on other sites

Fair enough if your box is being stripped for reconditioning, but if it's just for fitting that other gear it just seems a bit OTT!

Link to post
Share on other sites

Fair enough if your box is being stripped for reconditioning, but if it's just for fitting that other gear it just seems a bit OTT!

As i said you can do it whilst it's on the car. Hardly a massive job. Plus I'm sure if this was available for petrols they would jump on them. I can remember my sport sitting at 4krpm to do 70.

Link to post
Share on other sites

Alright tired, calm down, didn't notice you mentioned you could do in with the box in place.

Who is getting ruffled here? I was just reiterating just incase you didn't read it. Wasn't being arsey just trying to get some info across.

I'm sure mine is at 2000rpm @ 70mph standard.

You must have a different gear then. The arosa with EXB 02j geatbox will do 70mph at around 2.4-2.5krpm depending on wheel size.

Link to post
Share on other sites

Got my 0.658 gear fitted, Perfect for me. Sits about 2.1krpm at 70 on the speedo and 2,3krpm at 120kmh or gps indicated 70, I do alot of b road driving/commuting so the slightly higher rpm for me was worth it over the 0.622 gear which is like 2.1krpm at 80mph. The revs dropped too low to drive without feeling labored with the 0.622.

Edited by Dblock
Link to post
Share on other sites

Glad to hear it worked out for you :) Long motorway journeys are so much quieter now, I've yet to check the difference in MPG though but I fear it won't be such an accurate comparison because the longer gearing means I've been going a bit faster than I would have done with the shorter 5th in!

Ps. done some reading on remaps and I'm looking to get one done next year at insurance renewal time.

Edited by Midlands95
Link to post
Share on other sites

I wonder if a long 5th mod would work on an sdi....

I dont think you have the 02j gearbox. Also would it work in general as we are lowering 70mph to 2-2.2k thats a. so it's spinning less for better mpg and comfort but b. it's smack bang in the torque band. You would have to see what it's like in an sdi as if it's out of the torque band it might be worse on fuel and a slug to drive.

Link to post
Share on other sites
  • 6 years later...
On 11/24/2020 at 2:34 PM, Daniel1110 said:

 5th gear is short beacause when I go 140kmh the rpm is 3450k.

The fact you have high rpm's on 140km/h not always means only 5th gear is short - if the final drive is short, whole your gearbox will be short and 5th gear replacement will not help much.

You have 02T gearbox, you must write down gearbox identification letters, because there are a lot of 02T gearbox modifications. You can check some of the modifications and ratios of 02T gearboxes on this website.

37:50 is longest 5th gear I have noticed on 085 and 02T gearboxes.

Edited by ObjectiveAway
Link to post
Share on other sites
  • 4 weeks later...
On 12/18/2020 at 11:07 PM, Daniel1110 said:

I have HCS gearbox. What i need to change on my 02t transmission? Or replace full gearbox? 

EWT gearbox has 2,210 reduction, but HCS gearbox has 216mm clutch plate and 90mm flanges instead of 228mm clutch plate and 100mm tripod flanges on EWT gearbox, therefore they are totally not plug and play replacement. 

HCS have 37:50 5th gear sprockets and makes 2.672 reduction in top gear, which is around 2,5k RPMs on 60mph. There actually are one 085 gearbox with 36:51 sporckets, but I don't think this modification will give you much result for a lot of effort, if you will manage to get those sprockets on your gearbox.

Edited by ObjectiveAway
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.