Engine & Internal Chat about beefing up your engine's insides here.

Transmission swap?

Old 10-06-2009, 10:45 PM
Thread Starter
Join Date: May 2009
Posts: 4
Default Transmission swap?

Hello, i have a 98 accord v6 auto. i was wondering how to convert it to 5-speed if this can even be achieved and if so would it be a good idea since it has 190k miles right now or should i just wait till the trans. dies around 250k and ditch the accord... help?
Old 10-07-2009, 09:47 AM
JimBlake's Avatar
Super Moderator
Join Date: May 2006
Location: Wisconsin
Posts: 17,516

98 V-6 was never offered in manual tranny. The only reasonable swap would be a V-6 Acura (maybe the TL??) It's not exactly an easy swap, but search around here, I think theres some information.
Old 10-12-2009, 03:07 AM
Join Date: Nov 2008
Posts: 135


The Module
The swap module allows for the interfacing of the 6 speed manual transmission with the stock Accord 4 speed automatic transmission computer.

Without the module the following feature will not work.
-Full rev limit
-Reverse lock out
-Reverse light
-Passing inspection due to CEL

Parts list
The parts used for this swap are quite simple everything is available from Honda except the harness. Try to get as many parts off the donor car as possible. Here are some diagrams of the parts needed.

You can purchase parts and view detailed diagrams at Honda parts sites such as www.hondaautomotiveparts.com and www.acuraautomotiveparts.org. I find these are great sites for diagrams which allow you to see what is involved in a swap.

The only mounts that are required to be change are the transmission mounts. The rear engine mounts can also be changed with a CL-S mount which is stronger but is not required. For the transmission mounts use the ones from the 03 CL-S 6 speed.

Axles and Intermediate shaft
The stock axles and intermediate shaft work just fine with the 6 speed transmissions. The CL-S axles are suppose to be stronger and thicker.

You can use either the 03 CL-S or I4 Accord pedals.

Clutch hydraulics
You can use the clutch lines from the CL-S as well as the master cylinder. I have tried using a master cylinder from a mid 90's Civic as well and it works just fine and is a good bit cheaper.

Clutch Disc, Pressure Plate and Flywheel
You can use the clutch disc, pressure plate and flywheel from any 6 speed transmission. The Accord, TL and CL all use the same clutch but the CL uses a different flywheel which doesn't matter with this harness.

Shifter and Linkages
The I4 Accord shifter and linkages are not a direct fit and will have to be modified. The only linkages and shifter that are a direct fit are the from the 03 CL-S.

6 Speed Transmissions

6 Speed transmissions from the following cars can be used. But the Accord and TL transmissions will have to be modified slightly by welding on a stud for the shift linkage. (more on this later)
03-07 Accord V6 MT (NO LSD)
03 CL-S MT (LSD)
04-08 TL MT (LSD)

Special Preparations
Before installing the harness the mechanical aspects and stock wiring should be checked for functionality. This can done be driving the car in limp mode, by removing the transmission range switch from the automatic transmission and connecting it to the engine harness. Then by manipulating the the switch to the N or P position using a screw driver. Test to see if the car will drive. This will eliminate difficult troubleshooting due to the possibility of problems with both the car and harness.

Common Questions
Q: What car will this harness work on.
A: 98-02 Accord V6

Q: Will the harness work with a TL or CL.
A: Not yet we are working on the Type-S ECU currently. The harness might work on the 99 TL and will soon be tested.

Q: Can I use a I4 or Prelude transmission.
A: No only the listed transmission will work.

Q: Can I use this harness with the J32A2 Type-S ecu.
A: No, we are currently working on a harness that works with a Type-S motor. We hope this can be applied to the Accord, TL and CL.

Q: How can I get a harness.
A: The design has been modified for a easy install and will be mass produced soon. The first ones should be ready in around April.

Success Stories
Please let me know of any corrections.

Richie V6
99 Accord J30A1 with TL 6 Speed
99 Accord ECU

99 Accord J32A1 with Accord 6 Speed
99 Accord ECU

99 Accord J30A1 with CL 6 Speed
99 Accord ECU

99 Accord J30A1 with Accord 6 Speed
99 Accord ECU

2nd Gen Harness

**Orignal Post**
Hey guys, I am swaping in a 01 J30A1 and 6 speed into my 99 accord, since I bent my valves. This time I am working at home at a much slower pace so I will have time to take pictures and document the process.

So far I have prepped the new motor and removed the old motor from the car. I am waiting for my new clutch to come in. I will be running a distributor until I can figure out how to get a 01 ecu programmed by Honda.

As of September of last year I have been experimenting with swaping a 6 speed transmission into a 6th gen accord v6. As of last week I have designed, built and tested all the circuitry that solves all issues that people currently have with swaping in just a 6 speed tranny. Such as running check engine light and transmission fault free, working speedometer, vtec engaging and reverse shift lock out solenoid.

Several members have contacted me on building modules and harnesses that will allow them to run 6 speed tranny in there 6th gen accord. I was wondering how many people would be interested in this. I am planning on having custom printed circuit boards made and the larger the order the less expensive it will be. I am also thinking about offering a full swap kit with all the parts nesseccery for the swap including tranny. Basically you just pick up a pallet and all parts will be included.

I just noticed i have the resolution turned down really bad on my camera. The next set of pics will be more clear.

New motor, well only 28k

Stripped down to the bone

Stock harness

OOooOOOo J30A1 with 6 speed bolted to it

Tranny mount.

Hooked up

Front view

Rear View

No engine

Old engine meet your replacement

Tranny mount again

Unbolted CL-s 6 speed tranny


Creds to Richie v6
Old 02-28-2010, 02:23 PM
DSeng13's Avatar
Newest Of Newbies
Join Date: Feb 2010
Posts: 20

I know this thread is old, but not sure if someone would tell me to use the search feature if I made a new thread. lol

Anyways, I want to do the transmission swap as well and found a lot of info about it from many areas. The above post is also what made it seem realistic for me. I'd love to keep my car auto, but honestly I'd rather swap just to have a different tranny.

I want to know how people are doing these swaps though. Do they all have their own shops and equipment and the know how to do these swaps? Or do they bring them to a shop with all the parts and pay labor? I'd be more interested in the second option, but have no idea where I would go to get it done. Any advice appreciated thanks.
Old 03-01-2010, 09:34 AM
g22cd5's Avatar
Supper Moderator
Join Date: Feb 2009
Location: Tallahassee, FL
Posts: 3,894

You can take it to just about any shop. I had my dad's yota shop do my tranny when my auto blew out. Simple auto to auto swap shouldn’t cost you more then $500 total. I got mine done for $300 but that's just my dad works there. Since you want to stay auto I'm almost certain you can use a h22 tranny on your f23 engine I THINK. That will give you shorter gears and be a bit quicker. Now if you want a auto to manual swap well that will cost you ALOT more. When I did mine on my old cb7 I just bought beer and food for a couple of mechanic friends and did the swap in a weekend. That was in my home garage using jacks and jack stands it wasn’t fun but we got the job done.
Old 03-01-2010, 10:26 AM
DSeng13's Avatar
Newest Of Newbies
Join Date: Feb 2010
Posts: 20

My car has a j30a1 not f23, I'm guessing that eliminates the h22 tranny option? lol Not too sure, I'll look up more on that, but thanks for the tip about shops that takes some of the confusion away. It's also good to know mechanics can be lured with some beer!
Old 03-01-2010, 11:33 AM
JimBlake's Avatar
Super Moderator
Join Date: May 2006
Location: Wisconsin
Posts: 17,516

Yeah, H-series & F-series bolt up to each other. Not so with the V-6, it sits in the opposite end of the engine bay & spins the opposite direction. Look at certain Acura cars.
Old 03-01-2010, 12:19 PM
g22cd5's Avatar
Supper Moderator
Join Date: Feb 2009
Location: Tallahassee, FL
Posts: 3,894

yeah h22 tranny wont work as far as I know. My bad I was thinking you had a f23 not the v6 lol
Free beer and food they always love that..or maybe some sticky icky woo woo...they norm like that too
Related Topics
Thread Starter
Last Post
Engine & Internal
01-27-2013 07:41 PM
General Tech Help
05-09-2011 08:55 AM
General Tech Help
06-06-2010 09:33 PM
Engine & Internal
01-03-2006 11:52 AM

Thread Tools
Search this Thread
Quick Reply: Transmission swap?

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.