Transmission swap and speedometer change - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions


Reply
 
Thread Tools
  #1  
Old March 20th, 2009, 09:14 AM
slickrock
Status: Offline
Andrew Gold
94 D90
Member
 
Join Date: Jun 2007
Location: Los Angeles, CA
Posts: 5
Transmission swap and speedometer change

Hello. I have one of the first 94 NAS D90. I am not the original owner. I have been doing a bit of research and I still need some help. I currently have the R380 transmission. Previous owner mentioned swapping out the transmission years ago but couldn't remember the details. Wasn't the LT230 stock on a 1994? My speedometer is running about 3-5 mph faster than my actual highway speeds. Where do I find a different size gear? I will most likely need an extra tooth to slow down the drive on the speedo. Does anybody know of any manufactures that will sell a gear? Are there any other transmission manufacture parts that may fit and do the same job?
Thanks
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old March 20th, 2009, 09:26 AM
Hoosier's Avatar
Hoosier
Status: Offline
Chris Hinkle
More than I need
Member
 
Join Date: Jun 2006
Location: Dallas, TX
Posts: 634
Go to a speedo shop and they will splice in a little box with gears to correct the speedometer. At a later date - if you change tires, etc - they can change the little gears to correct for the changes. Or you can go the electronic route with a newer transfer case and a VDO programable speedo.
Reply With Quote
  #3  
Old March 20th, 2009, 10:47 AM
evilfij's Avatar
evilfij
Status: Offline
evilfij
I have never seen a rover in person
Member
 
Join Date: Oct 2003
Location: on the internet
Posts: 14,688
"Wasn't the LT230 stock on a 1994?"

LT230 is the transfer case. Stock transmission on most 1994s was an LT77. Not sure of the cutoff number but it was around 1300. Nearly all have been upgraded to the R380, many got it under warranty when newish.

"My speedometer is running about 3-5 mph faster than my actual highway speeds."

This is normal and designed to be that way.
__________________
*not legal advice*
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old March 20th, 2009, 11:23 AM
Uncle Douglas's Avatar
Uncle Douglas
Status: Offline
Doug Crowther
A defender in every driveway-motto
D-90 Source Vendor
 
Join Date: Dec 2007
Location: Gods Country- Central Virginia
Posts: 11,841
Registry
3-5 is good. Mine is off a consistent 10% per the gps
__________________
Good judgement comes from experience,experience comes from bad judgement.

Dividing Creek Imports
Worldwide Vehicle Shipment and Importation Service
Restoration & Modification work


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

410.693.1391


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote
  #5  
Old March 20th, 2009, 11:31 AM
Hoosier's Avatar
Hoosier
Status: Offline
Chris Hinkle
More than I need
Member
 
Join Date: Jun 2006
Location: Dallas, TX
Posts: 634
Actually, problem is the computer. In 94 with the mechanical.speedometer, there is a sensor about a foot from the transfer case that detects the rpms of the speedo cable and sends a signal to the computer - which limits speed. When we changed gears from 3.56 to 4.75 - fuel would be cut off about 65 or 70 mph (depending on tire size). Computer thought we were trying to go over 90 mph. Anyway, you could get a speedo shop to put stepdown gearbox before the sensor to correct the rpms of the cable and prevent fuel cutoff. When you go to a 300tdi and lose the computer, you can bolt up a sensor from a 97 defender directly to the transfer case and use that signal for the VDO speedometer. I haven't tried the 97 sender in a 94 and sending that signal to both the computer and an electronic speedo - it might work - but I already had the stepdown box.
Reply With Quote
  #6  
Old March 20th, 2009, 11:49 AM
ECR's Avatar
ECR
Status: Offline
East Coast Rover Co.
Just Defenders, nothing else.
D-90 Source Vendor
 
Join Date: May 2006
Location: Rockland, ME, USA
Posts: 4,614
Quote:
Originally Posted by slickrock
Hello. I have one of the first 94 NAS D90. I am not the original owner. I have been doing a bit of research and I still need some help. I currently have the R380 transmission. Previous owner mentioned swapping out the transmission years ago but couldn't remember the details. Wasn't the LT230 stock on a 1994? My speedometer is running about 3-5 mph faster than my actual highway speeds. Where do I find a different size gear? I will most likely need an extra tooth to slow down the drive on the speedo. Does anybody know of any manufactures that will sell a gear? Are there any other transmission manufacture parts that may fit and do the same job?
Thanks
Use the speedo drive gear form a RR Classic, FRC9339 is the part #. It will cure your roughly 5 mpg overread issue.
Cheap and easy and no need for any custom work.
Most NAS 90s came with the tan drive gear that reads too high. The Black RR Classic gear corrects the issue with 2 more teeth.

Follow-up Post:

Quote:
Originally Posted by evilfij
"My speedometer is running about 3-5 mph faster than my actual highway speeds."

This is normal and designed to be that way.

WTF
No it wasn't.....
Getting the speedo to read correctly is simple and easy.
__________________
Email:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

I do not check PMs. Call or email if you need something.

ECR is not a parts source. We are not in the mail order business.
Reply With Quote
  #7  
Old March 20th, 2009, 11:57 AM
evilfij's Avatar
evilfij
Status: Offline
evilfij
I have never seen a rover in person
Member
 
Join Date: Oct 2003
Location: on the internet
Posts: 14,688
Quote:
Originally Posted by ECR
WTF
No it wasn't.....
Getting the speedo to read correctly is simple and easy.
Yes, it is. The odometer on every rover I have owned is near spot on accurate, while the speedos all read a bit fast. This is common and is "designed" into many vehicles. Do a quick google search.

If you put the RRC gear your odometer will be off, and I believe it will overcorrect and your speedo will be slow.
__________________
*not legal advice*
Reply With Quote
  #8  
Old March 20th, 2009, 12:02 PM
ECR's Avatar
ECR
Status: Offline
East Coast Rover Co.
Just Defenders, nothing else.
D-90 Source Vendor
 
Join Date: May 2006
Location: Rockland, ME, USA
Posts: 4,614
Quote:
Originally Posted by evilfij
Yes, it is. This is common and is "designed" into many vehicles. Do a quick google search.

If you put the RRC gear your odometer will be off, and I believe it will overcorrect and your speedo will be slow.

If that is true it is the stupidest thing I have ever heard.
Why design a system to be wrong?
What is the purpose of that?

My own truck has a RRC black gear and it is spot on with 265/75s according to the GPS.
__________________
Email:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

I do not check PMs. Call or email if you need something.

ECR is not a parts source. We are not in the mail order business.
Reply With Quote
  #9  
Old March 20th, 2009, 12:11 PM
evilfij's Avatar
evilfij
Status: Offline
evilfij
I have never seen a rover in person
Member
 
Join Date: Oct 2003
Location: on the internet
Posts: 14,688
"If that is true it is the stupidest thing I have ever heard.
Why design a system to be wrong?
What is the purpose of that?"

Liability. If you had a speedo that was reading 5% slow and spun out you could sue. 5% high and it will never be an issue. At least in Germany the law is it cannot read slow (ever, worn tires etc.) but can be 5-7% fast.

Five years ago, my brand new 2004 BMW was the same way as my rovers a few percentage points high which is when I started looking into the issue. Interestingly, in the rovers and the BMW, the odometer was dead nuts accurate (probably because if it was not, someone would sue for you making their warranty expire before it "really" hit XXXXX miles).

Ron

Follow-up Post:

Quote:
Originally Posted by ECR
My own truck has a RRC black gear and it is spot on with 265/75s according to the GPS.
Does your odometer read high or no? RRCs had ~29in tires and D90s have ~32in tires, it should make up for more than 5% changing to the RRC gear.
__________________
*not legal advice*
Reply With Quote
  #10  
Old March 20th, 2009, 03:06 PM
Stmpede's Avatar
Stmpede
Status: Offline
Andrew Najarian
'93 NAS D110 #43
Member
 
Join Date: Mar 2007
Location: Jacksonville, FL
Posts: 2,459
Yeah, BMW's I believe are designed to read app. 5% high. Every vehicle I have ever owned reads a couple MPH higher than the radar stations the police park on the side of the street. As others have said, it is for liability. In addition to what has been mentioned, if you got a speeding ticket because your speedo was reading high you could sue the manufacturer also, so...they purposely make them read slightly high.
__________________
"I have taken more good from alcohol than alcohol has taken from me." - Winston Churchill
Reply With Quote
  #11  
Old March 20th, 2009, 05:25 PM
Uncle Douglas's Avatar
Uncle Douglas
Status: Offline
Doug Crowther
A defender in every driveway-motto
D-90 Source Vendor
 
Join Date: Dec 2007
Location: Gods Country- Central Virginia
Posts: 11,841
Registry
[QUOTE=ECR]Use the speedo drive gear form a RR Classic, FRC9339 is the part #. It will cure your roughly 5 mpg overread issue.
Cheap and easy and no need for any custom work.
Most NAS 90s came with the tan drive gear that reads too high. The Black RR Classic gear corrects the issue with 2 more teeth.

Neat piece of information. Thanks for sharing it.
__________________
Good judgement comes from experience,experience comes from bad judgement.

Dividing Creek Imports
Worldwide Vehicle Shipment and Importation Service
Restoration & Modification work


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

410.693.1391


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote
  #12  
Old March 20th, 2009, 06:00 PM
ECR's Avatar
ECR
Status: Offline
East Coast Rover Co.
Just Defenders, nothing else.
D-90 Source Vendor
 
Join Date: May 2006
Location: Rockland, ME, USA
Posts: 4,614
Quote:
Originally Posted by Maryland 110

Neat piece of information. Thanks for sharing it.
If you have a ROW truck it is even easier to get the speedo right, as they offer many more varations of gears with different number teeth. Sadly the EFI trucks are limited as only the tan and the black drive gears have the right size opening for the EFI speedo cable, the rest are larger for Tdi and other ROW models (those have a larger inner speedo drive cable).

Follow-up Post:

Quote:
Originally Posted by evilfij
Liability. If you had a speedo that was reading 5% slow and spun out you could sue. 5% high and it will never be an issue.
OK, sadly that makes sense.
What a F'd up world the scum-bag lawyers and the morons who can't take the blame for spilling coffee on themselves have created... sad legitinous mess.
__________________
Email:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

I do not check PMs. Call or email if you need something.

ECR is not a parts source. We are not in the mail order business.
Reply With Quote
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Tags
speedo, transmission

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
VDO Gauge Parts/Installation/Problems Merged Threads TDI Guy Smaller Projects 355 October 15th, 2017 02:59 PM
Newbie Questions (please don't haze me!) Wolf Fabrication Misc. Chit-Chat 15 September 29th, 2007 10:45 PM
Correcting speedometer after lift/tires Seriesman Defender Technical Discussions 16 November 24th, 2005 08:37 PM


All times are GMT -5. The time now is 05:04 PM.


Copyright