[tdij]

I can't really shed much light to the 4bt debate. Although that was the initial plan for my YJ, I am very happy I opted for the TDI in my jeep instead.

I put a 98 TDI in my Jeep this winter, so it is a relatively new swap, however I have about 6K miles on it I believe.

I can't offer any perspective on the HPA kit, as I was instantly turned away by the price.

How I adapted it:

Acme specializes in TDI swaps into Suzuki's. You can pretty much buy adapters, motor mounts, and everything else you would need for a bolt in swap... for a zuk! Not in my future.

Don't own a zuk? well... zuk guys often upgrade to toyota drivetrains, thus Acme has developed a bellhousing adapter for the toyota transmissions. This worked out great for me, as I was considering toyota axles, and decided to just run a full toyota drivetrain.

I know... I know...

Anyways... here is where it gets interesting for Jeeps: Toyota and Jeep manual transmissions are based off the same core unit. You can adapt either to mount up to the opposite engine or transfer case. In order to adapt an ax-5 to a toyota engine(or acme adapted TDI) you need an input shaft and bellhousing off of a 4cyl toyota transmission. In order to adapt an ax-15, you need an input shaft and bellhousing off a 4cyl turbo toyota transmission.

That being said, you can adapt a tdi (or any vw 4cyl engine for that matter) to your jeep transmission for far less then the $1300 HPA charges for their transmission adapters. Down side is you might not be able to use their engine mounts and stuff, as it will likely put the engine at a different position in the engine bay front to back(just an assumption) However... if $1500 for engine mounts isn't out of the question... then the 1300 for their adapter shouldn't be either I suppose.


On to my experiences with it:

For reference, a little about my jeep. I pulled a 4.0 with over 300k out of it which ran great with no mechanical concerns. It likely wasn't as powerful as a lower mileage 4.0 considering the miles, but it was solid. I have 35 m/t tires and 4.88's. I also live in the rockies and do a substantial amount of 7% grades at highways speeds for long durations.

As far as power goes...

i put a '98 TDI in, and am impressed with the power so far. I have not tuned the TDI or otherwise modified it in any way other then removing the EGR, and it has about 180k on it, so still not a "low" mileage engine. By the numbers on paper the TDI is significantly underpowered compared to the 4.0, however experience says it is VERY COMPARABLE. I would call it a wash all in all. The TDI's power is at low rpms, and therefore you have access to it at all times, whereas you have to be wrapping out the 4.0 to actually be getting the power equivalent to the numbers. I can say that my TDI climbs the mountain passes here in the rockies at about the same speed as the 4.0 did give or take a few mph. The difference is that the TDI does it in 5th while I would have been bouncing between pegging third and slowing down in 4th with the 4.0. Only one other Jeep owner has driven it... and his impression was the same as mine compared to his TJ on 33's. I am greatly looking forward to chipping the ecu and bigger nozzles. I'll have significantly more power than you'll ever get out of a NA 4.0.

Now to mileage...

To establish my driving style, I am one of those guys that got 11-12 mpg with my 4.0, and I have not babied the TDI at all. If anything I have driven it harder... trying to make any bugs from the build show.

So far it has been an extremely consistent 27mpg, with no more than 1 mpg variance on any tank but one. That is tanks with only city, and tanks with only highway(not typically faster than 65-70), and tanks with mixed... all 26-28. I had one tank where I drove for about 200 miles at 80 over a couple thousand feet elevation gain, and then did another 60 miles with about 4000 additional feet in elevation gain. This tank earned me a still respectable 20mpg. All mileage is based off of GPS as I don't actually have a speedo hooked up yet.



As far as the intercooler goes, I am running a rather large (by tdi standards) air to air. I have only wheeled with this one day so far, however had no issues with intake temps. I am in agreeance that it doesn't matter air-air or air-water, as either way... with not air passing through the intercooler or the intercooler systems radiator you will be at risk of heat sink. My solution to this will be simple if I find I have a problem with it (maybe desert wheeling), simply a fan on the intercooler with a dash switch. Problem solved... after all... that's how your engine cooling system deals with the problem of heat sink.

To the OP... or anyone interested in it... feel free to hit me up with any questions... or follow the link in my sig to check out my build on pirate.

[tdij]

Oh, and to put my opinion in on the money end of things... My swap was done with a full transmission, dual case, axles, suspension change, along with frame shortening, and significant body modifications. As a result my build was much more expensive then just a TDI swap alone would be... so how much I spent is irrelevant to this engine swap even if I had kept track.

As far as money saved in fuel after the swap... based of my mileage experiences, and gas/diesel prices in my area at the time, I will save $5000 every 30K miles. Sure there are always other factors such as maintenance, vw parts cost vs jeep parts, and fluctuation of fuel prices... but purely fuel considerations based on current prices say a lot about how long it would take to pay off my swap!

Yes... I largely did this simply because I could, because it was fun, and because I like the uniqueness of it... however it is very possible to do this swap for the financial benefits!

[LittleBluE]

Originally Posted by chris86vw

Not saying you can't buy why? (and I have dream built one in my head many times so I like the idea of it..)

the 4bt is the same engine with 2 cylinders lopped off. Hell my intake and exhaust manifold are modified 12V pieces. So it is just as bullet proof.

The 4bt with intercooler and accesories is already about 400lbs more then the 4.0. The 12V will be close to 750lbs heavier. That is a lot of weight for little gains over other options.

It will fit but will take a lot of work. This is the 4bt in mine with no body lift. The engine is IN the firewall, like I can't take the trans out unless i pull the entire drivetrain because there is no room. When I had the wrong passenger side mount in and it collapsed slightly the engine was actually resting on the firewall. I did a body lift just to get AC in since my turbo location blocked the factory lines at the firewall, but it ended up being a blessing since now I think I can pull the trans by itself (maybe) and its no longer rubbing. A 12V would be extremely tight in the front, the location of my engine puts the trans and transfer case about 1" forward of stock just to get the back of the engine to fit around the firewall. The 12V would sit the same and just mean you need another foot of room up front which there isn't.

IT can be done but I see little reason other then bragging rights over the 4bt.

I see reason because I happen to love HP and torque and the 12v IS capable of massive numbers. I race diesel trucks. I want power and I'll damn right have plenty of it.

I want the uniqueness. I want the challenge. I want the bragging rights

[DeltaBCTJ]

Alright so I took the YJ for a drive.

Holy @#$! that thing moves! Even with it weighing in at 4,000 lbs I had no problem boogeying through traffic. The best part is how freaking stock it seemed. It was quieter then the 6 other when its in boost. At that point its just the woosh of the turbo. This thing only had an AX-5 in it and it was holding up just fine after a few years of being like that.

Obviously on such a short drive I cant test fuel mileage, however they report mid twenties around town and ~30ish on the highway. Pretty good numbers for the old rolling shoebox. For something that isn't looking to enlarge the look of a penis for bragging rights and wants something that makes the Jeep better in every way the TDI seems to be the way to go in my opinion.

The guys at HPA are great and answered any questions I could have. Glad I came in when I did as the Sema truck is going somewhere else and they are building up a TJ this time with their new 'truss member'

[LilSteve97TJ]

Here is a thread that was happening a few months ago about this same swap. I say go for it i'd be down with doing it would be a fun and usuable swap. There will be a lot of people on this forum who will say anything thats not a 5.3 is stupid....hater's will hate.


http://www.jeepforum.com/forum/f9/di...ports-1130432/

[clintrivera]

Originally Posted by DeltaBCTJ

Alright so I took the YJ for a drive.

Holy @#$! that thing moves! Even with it weighing in at 4,000 lbs I had no problem boogeying through traffic. The best part is how freaking stock it seemed. It was quieter then the 6 other when its in boost. At that point its just the woosh of the turbo. This thing only had an AX-5 in it and it was holding up just fine after a few years of being like that.

Obviously on such a short drive I cant test fuel mileage, however they report mid twenties around town and ~30ish on the highway. Pretty good numbers for the old rolling shoebox. For something that isn't looking to enlarge the look of a penis for bragging rights and wants something that makes the Jeep better in every way the TDI seems to be the way to go in my opinion.

The guys at HPA are great and answered any questions I could have. Glad I came in when I did as the Sema truck is going somewhere else and they are building up a TJ this time with their new 'truss member'

If it only had an AX-5 and was holding up great I have to raise an eyebrow at how much power it puts out - since people kill the AX-5 with a stock 4 banger on a regular basis.

[chris86vw]

Originally Posted by clintrivera

If it only had an AX-5 and was holding up great I have to raise an eyebrow at how much power it puts out - since people kill the AX-5 with a stock 4 banger on a regular basis.

Most manual transmissions don't fail directly because of too much power they fail because of how the power is applied by the idiot in the driver seat.

150hp flat out on the highway at 3K rpm is a lot different then 300ft/lbs of torque at 1500rpm with the rear bound up on a rock and the front end bouncing around.

It very well could be (i doubt it on a 1.9 without turbo and injector upgrades) making the power claimed with the ax5 perfectly safe behind it since they are not necessarily using it for the same things you are.

I ran a stock clutch for 80K miles in my A3, 40k+ was with the gt35 and running 30+ psi making over 600hp. Yet people with stock turbos making 250hp were smoking clutches with a few k on their cars. The differences was how I drove it compared to them. I had no low end I never dropped the clutch and tried to launch at a light, that is what killed the stock clutches not a specific amount of power being applied smoothly at 60mph.

[clintrivera]

Transmissions and clutches are rated to a specific torque value. Most are rated conservatively and you can "usually" get away with 20% or so more torque than the rating.

You put enough torque through a transmission or a clutch and it will fail. It doesn't matter the manner in the torque was applied, to a clutch or a transmission, 300 ft pounds of torque is 300 ft pounds of torque.

I sold my AX5 to a guy that broke his 3rd AX5 in his Cherokee. He was an older retired guy that never went off road and never towed.

So even if the 1.9 TDI was a good swap for a wrangler (it isn't) the AX5 isn't a good transmission to go behind it, or even the stock 4 banger.

[Hammond_Egger]

Originally Posted by clintrivera

So even if the 1.9 TDI was a good swap for a wrangler (it isn't) the AX5 isn't a good transmission to go behind it, or even the stock 4 banger.

Hey, I am a ten penny nail in use of a staple guy myself, but I am going to call Bull$*%# on this. If you are planning on punching the snot out of you Jeep, then maybe it is not right for you, but based on all of the AX5's out there still running after 200K, your point is not valid.

Also, I think the 1.9 TDI is a good swap in the Wrangler. Not all of us need the power of the 5.3 for what we do with our Jeeps.

Glad you found the right combo for how you are using YOUR Jeep, but it does not mean other options are "not good".

Take my 2 cents for what it is worth

[chris86vw]

Originally Posted by clintrivera

Transmissions and clutches are rated to a specific torque value. Most are rated conservatively and you can "usually" get away with 20% or so more torque than the rating.

That is an arbitrary value you literally pulled out of no where to attempt to seem like you had valid input on the subject.

20% means nothing especially when you attempt to claim some old guy in a street jeep keeps blowing up a trans on stock power. I know more applications that can take 100% more then what they are rated for then 20%..

Yes I am 100% aware that power can cause damage, never said it didn't. All I said was that most of the time from my experience (this is what I do for a living) abuse or application is the common factor in failure not power.

Just because you put X amount of torque to a trans does not mean the load on the parts themselves is the same in all conditions.

I can hit your hand with a 5lbs hammer while its in the air or I can hit your hand with a 5lbs hammer while its laying on a concrete surface, which one is going to cause more damage?

[clintrivera]

Originally Posted by Hammond_Egger

Hey, I am a ten penny nail in use of a staple guy myself, but I am going to call Bull$*%# on this. If you are planning on punching the snot out of you Jeep, then maybe it is not right for you, but based on all of the AX5's out there still running after 200K, your point is not valid.

This is what Christian Hazel (JP magazine) says about the AX5:

A The AX-5 found behind 2.5L four-cylinder engines is okay at best. However, we can't see ourselves ever rebuilding one, so it's hard to recommend our readers do the same.

Novak conversions:

The AX5 is prevalent, but sadly it's strength is minimal, making it a questionable off-road transmission. Failures behind even stock engines are not uncommon.

Advanced adapter covers most transmissions in their tech vault, but has nothing to say about the AX5. The AX5 is classified as a light duty transmission. It also has a serious issue with 5 gear going out.

There are plenty of Jeeps running around with D35's and high miles too. Doesn't make it a strong axle does it?

Originally Posted by Hammond_Egger

Also, I think the 1.9 TDI is a good swap in the Wrangler. Not all of us need the power of the 5.3 for what we do with our Jeeps. Glad you found the right combo for how you are using YOUR Jeep, but it does not mean other options are "not good".

The 1.9 TDI isn't a good swap in a Wrangler. In stock form, it puts out less power than the 4.0 and has less of an RPM range, meaning gearing is more important. Modified, sure it may make more power at the expense of more money and less reliability.

Sure it gets better gas mileage than the 4.0, but at what cost? Thousands for the swap and hours of custom fabrication?

If it was a good swap Novak and Advanced adapters would be all over engine mounts, radiators, adapters, etc. More people would be doing them. I love reading about engine swaps. I can only recall reading about one or two completed, running swaps.

I would have swapped a diesel into my Jeep. The cost / benefit wasn't there.

There are a few other options that make sense to swap into a wrangler, and I carefully considered each one.

Dodge magnum 5.2 / 5.9
Hemi
Ford 5.0
Jeep 4.0 (from a Jeep 4.0)

Sure not everyone wants or needs the power of a 5.3, but you have to ask yourself - why are you swapping the engine you have now in the first place?

[clintrivera]

Originally Posted by chris86vw

That is an arbitrary value you literally pulled out of no where to attempt to seem like you had valid input on the subject.

20% means nothing especially when you attempt to claim some old guy in a street jeep keeps blowing up a trans on stock power. I know more applications that can take 100% more then what they are rated for then 20%..

Yes I am 100% aware that power can cause damage, never said it didn't. All I said was that most of the time from my experience (this is what I do for a living) abuse or application is the common factor in failure not power.

Just because you put X amount of torque to a trans does not mean the load on the parts themselves is the same in all conditions.

I can hit your hand with a 5lbs hammer while its in the air or I can hit your hand with a 5lbs hammer while its laying on a concrete surface, which one is going to cause more damage?

The 20% value is something that I've seen in a few magazines. I suppose it doesn't matter in this case since Aisin doesn't even give rated torque values for the AX5 or AX15 only stating the AX5 is a light duty transmission and the AX15 is a medium duty transmission.

In a failure where a transmission does break (ie: break teeth, shatter a shaft, crack a case, etc) the maximum torque for the weakest part was exceeded.

The reason why I wouldn't want to have my hand hit with a hammer (swung with the same force) against a concrete surface is because the majority of the force is being transferred to the hand - where in the air it is being dissipated and transferred to motion.

Same goes with cars VS off road vehicles. Its hard to transfer the maximum torque output of a car when you are limited to available traction.

Off road, you aren't really limited to traction if your tire gets wedged between rocks. In this situation you can even apply the maximum torque to the parts downstream from the engine.

If the weakest link can only withstand 300ft pounds of torque before it breaks, it doesn't matter the manner it was applied.

[chris86vw]

Originally Posted by clintrivera

The reason why I wouldn't want to have my hand hit with a hammer (swung with the same force) against a concrete surface is because the majority of the force is being transferred to the hand - where in the air it is being dissipated and transferred to motion.

IF you get this then why is it so hard for you to understand that how the vehicle is being used is what defines the limitations of hte hardware and why they can make the power they are through the Ax5 when used how they use it.

You don't like diesels in jeeps.. glad you feel the need to interject in every thread about them telling people they are stupid. We can all now be saved..

[clintrivera]

Originally Posted by chris86vw

IF you get this then why is it so hard for you to understand that how the vehicle is being used is what defines the limitations of hte hardware and why they can make the power they are through the Ax5 when used how they use it.

You don't like diesels in jeeps.. glad you feel the need to interject in every thread about them telling people they are stupid. We can all now be saved..

I completely agree with you. You can make as much power as you want, and as long as you don't use the power you'll never break anything.

Kinda pointless though? Kinda like spending $6000 on implants for your wife and making her wear loose fitting sweaters and turtlenecks.

I was into Samurai's before Jeeps. That would be a good platform for a TDI since they way far less than a Wrangler, and it has been done before so there is lots of support.

I love diesel, there just aren't any in the US that make sense to swap into a Wrangler.

I would love to have the 2.5 or 3.0 out of a grand or liberty, but they are very rare, cost a mint, no adapters, mounts, basically you are on your own.

For that vast majority of people here on JF (IE: middle class people on a reasonable budget) swapping a USDM diesel engine makes no sense whatsoever.

If you have money falling out of your pockets, or own a shop that's a whole different ball game. The JK that MBRP built with the 12V cummins is one of the baddest rigs I've seen. I'm not sure many people on here could write a check for that though.

[chris86vw]

Originally Posted by clintrivera

Kinda pointless though?

No because your intentions for a vehicle are not necessarily the same as the next guy.

You have not proven that the AX5 can't hold the power of that engine, you have simply provided examples of people who say that if you wheel it hard it won't hold up. That isn't everyone's plan for their vehicle, nor is it necessarily what HPA or their customers are doing with it.

You have provided no evidence at all of an actual torque rating for that transmission to base your claims from either.