What's new

Bolting Dodge 3.9 (or others) to R150/151F using factory parts

IowaOffRoad

King shit of turd island
Joined
Feb 19, 2021
Member Number
3513
Messages
1,042
Loc
Under the apple tree
I have read this possibility on various 'Yota specific forums, but I have never seen the evidence of it being done... UNTIL NOW!

In addition to off-roading Toyota's, I also enjoy Ma Mopar's products. As I can't afford (read-cheap bastard) the good Toyota stuff, I have always been fascinated with the idea of adding more power to the rig without going the adapter route. As everybody on both sides of the Pacific used the R series Toyota/AX series Dodge/Jeep/AR series GM/MU5 Isuzu Aisin transmission, I have read several forum posts about the viability of this swap. I recently jerked the 3.9L Magnum and AX15 out of a '96 Dakota with the intent of using these parts to get the Dodge engine happy with the 'Yota drivetrain. It's not running yet, but I now know that the conversion of the trans isn't as easy as some internetters would make you believe, but doable with basic hand tools and some mechanical experience.

First, you need an AX15 with the appropriate bellhousing. If you were so inclined, you could use a Jeep AX15 as well with the Dodge belhousing as the input shaft is the same, at least for the years I have been handling. I won't explore the sacrilege of bolting a 4.0L engine in a Toyota, but it is doable. I am using a Dakota with an external slave as god intended, but for argument sake you could use an infernal slave setup. Pull the bell off the Dodge trans, pull the input shaft bearing retainer, pull the snap rings, both on the shaft and on IP bearing and countershaft. Pull shifter, pull bolt out of shift rail, pull rail after pulling plug on back housing, rotate shift fork out of the housing, remove case half bolts, split case halves off of center support. Then, you are going to have to pull the keeper off the overdrive shaft, pull bolt out of 5th gear fork, pull gear (will need puller, 2 threaded holes in this gear to do this), pull bearing/shaft retaining plate off of rear shaft, pull reverse shaft/gear, pull snap ring off of counter shaft, slide out rear countershaft bearing. Should be able to pull input shaft and gear after you can move countershaft.
Then, pull down R150/151F in the same manner. The only differences I spotted is the output shaft (obviously) and the fact the overdrive gear is held on with a staked nut vs. a keeper, and there is a small ball in the shaft with a retainer before the countershaft rear bearing. Otherwise they are identical.
Then, install Dodge input shaft on Toyota trans, reassemble. Install Dodge input shaft bearing retainer and bellhousing on Toyota case. Use Dodge clutch components. I don't have it installed yet, but I'm planning on adapting the factory Dodge slave to the Toyota master. Hoping a DOT compression fitting will handle the pressure on the factory plastic hose from Dodge.

I have attached a photo of the assembled with the Dodge input shaft on the Toyota geartrain. I didn't think to document with photos, but I don't think you should attempt this unless you've had prior experience successfully dismantling/reassembling manual transmissions. I have done more than a few. If you have some experience, the process is relatively straightforward. Just be careful not to mix/match too many of the components, while functionally identical, they are worn in to their current trans. In my younger/poorer days, I've built a few frankentransmissions out of several parts boxes. If you're careful, they work wel, but can be noisy and make metal. I would recommend anyone doing this should change the oil a couple times with engine oil changes to monitor new gear break-in.

As I'm anti-social, I may have to poke a 4.0L six in a Toyota using this method. No denying they are a good engine, but I don't think I could stomach it for very long. Other options are the Isuzu engine that this transmission came with, either 2.6-4 or 3.1/3.2 V6. Probably not the best option. Not sure which engines GM installed in front of their Aisin variant. The internet says they used it, but I have never seen or heard one, and not sure what the application would be. May not even have been sold here. If anyone reading this far knows, please point me in the right direction.

BTW as the 3.9L Dodge shares architecture and rear bolt pattern with the small block V8's, with a 10.5 inch flywheel you should be able to run one of those as well. I wanted the V6 to keep it light and simple, as I'm sticking it in a 3400# pickup.

I still think this is at least more interesting than SBC/LS swap that everyone does to everything.
 

Attachments

  • Dodge input shaft on Toyota geartrain.JPG
    Dodge input shaft on Toyota geartrain.JPG
    2.4 MB · Views: 125
On the old site, many years ago, someone stuck a Jeep 4.0 in a Toyota. Don't remember what the rest of the drivetrain was, but it was done.
 
I was never a member of the old site, though I have found a lot of info on their in the past. I'm absolutely sure someone, possibly many someones, have done something similar, or the same. I just have never found someone who'd actually done it on the internet in 8-10 years of looking. I would be interested to see that post if someone knows where to find it. It sucks so bad trying to find anything on there now.
 
I was never a member of the old site, though I have found a lot of info on their in the past. I'm absolutely sure someone, possibly many someones, have done something similar, or the same. I just have never found someone who'd actually done it on the internet in 8-10 years of looking. I would be interested to see that post if someone knows where to find it. It sucks so bad trying to find anything on there now.
It had to be more than 10 years ago, I vaguely remember it.
 
There was two builds. It’s the length of the motor that was the issue.

there was a guy who built a newer Colorado up here that used factory shit supposedly to bolt in Toyota tranny and tcase.
 
There was two builds. It’s the length of the motor that was the issue.

there was a guy who built a newer Colorado up here that used factory shit supposedly to bolt in Toyota tranny and tcase.
Just did some internet searching. Apparently the MA5/AR5 used in the 2005-up Colorado/Canyon/Solstice was a slightly updated version of the AX15/R150 trans. Some different gear ratios than any of the Jeep/Toyota variations. Apparently, the OD gear setup was slightly different. Bellhousing and input shaft bearing retainer look to bolt on the same too. With 4th gear being straight through and seeing no changes in the colorado parts diagram up front, perhaps what I did with the Dodge can be done with the GM. Why you would want to put one of those engines in a Toyota with the added complexity and not a real gain in power or commonly available parts, I don't know. I guess if you want to put a Toyota solid front in a Colorado, it's probably cheaper than an Atlas T-case. Main reason I liked the 3.9L Dodge is parts availability is about as good as a Chevy, without the belly-button stigma. Still fairly light compared to other engine swap candidates. I know an LS doesn't weigh much with the aluminum heads, but I think that kind of power would cause me to spend more $$$ on drivetrain, where an American V6 swap seemed a good balance of power and reliability without generating too much breakage downstream.
 
I’m contemplating a 1GR-FE swap. Those engines have been around for 19 years so there are lots available. Just need to do more research.
 
Top Back Refresh