Putting a diesel into an AWD Astro Van

[Pengyou]

I have a dream...maybe an obsession I would like to buy an older AWD Astro van and put an inline 6 cylinder diesel engine in it. I have seen some that are about 4.2 liters - the Toyota and Nissan. The Toy is an awesome engine, but it also has a price with Bible proportions - seems at least $6K for a used one. I have seen the Nissan for around $3K. Can anyone comment on the durability of these engines? They are pretty close to the power of the gasser in the van but put out more torque than it does. I am leaning to the I6 because I have heard (anecdotally) that they are much smoother and quieter than a 4 cylinder, say a 4bt. What am I hoping to accomplish? A little better fuel economy, a simpler engine/tranny (a non electronic engine and tranny) and hopefully the ability to use biodiesel. Any comments?

 

[Buddha.]

Isn't the Astro a unibody? If you keep the tire size modest a VW ahu might be alright but I'm not sure theres adapters to a chevy trans

 

[Stroverlander]

Diesel swap has been done (posted here and ASV) with a Mercedes diesel though not awd. Would and inline six even fit? I also just don't see the cost benefit of such a swap. While fuel economy may be improve slightly, that is obviously offset by the cost of swap. While the engine may be simpler electronically, that is also offset by the complexity of the swap and having a bunch never tested, one-off parts.

Sorry to be a negative Nancy, I suppose it just doesn't appeal to me knowing that the factory setup is rather solid and cheap (other than mpg). My preference would be to just do a V8 swap if I thought mpg could be improved, not made worse.

 

[Stroverlander]

Isn't the Astro a unibody? If you keep the tire size modest a VW ahu might be alright but I'm not sure theres adapters to a chevy trans

Front subframe / unibody

 

[QCAuto]

What about the Mercedes, ,OM617, turbo 5cyl, have sent them in Toyota, land rover discovery and jeep yj so far. Going to be tons of work!!

 

[T.Low]

Diesel swap has been done (posted here and ASV) with a Mercedes diesel though not awd. Would and inline six even fit? I also just don't see the cost benefit of such a swap. While fuel economy may be improve slightly, that is obviously offset by the cost of swap. While the engine may be simpler electronically, that is also offset by the complexity of the swap and having a bunch never tested, one-off parts.

Sorry to be a negative Nancy, I suppose it just doesn't appeal to me knowing that the factory setup is rather solid and cheap (other than mpg). My preference would be to just do a V8 swap if I thought mpg could be improved, not made worse.

I have to agree.

Buy and all-wheel-drive Astro and drive it. Take your diesel swap budget amount and invest it in the market. You will be ahead.

 

[Mwilliamshs]

An inline 6 will be very tight where the biggest engine originally installed was only 3 cylinders long (v6 = 3 on each side, I-6 = all in a row).

If you want a diesel Astro consider that small block Chevy v-8s are a reasonably easy fit (4 cylinders on each side) and that a 4.3 is really just a 5.7 with 2 cylinders cut off the back. The v8 swap is VERY well documented and basically plug and play.

Now consider that GM has a diesel designed to replace their 5.7 gas engine very easily, the 6.2/6.5 Detroit. These are not powerhouses but neither are the Toyota/Nissan mills you'd mentioned. They are very very fuel efficient and have the balls for suburbans, trucks, etc so a mid-size van should be small potatoes.

These engines do have quirks but can be exceedingly reliable and perform well for you just as they do in military Hummers.

Typical Astro 4.3 = 165 hp/ 235 lb-ft

Typical 6.2 non-turbo (Easier to package in the van)= 165hp / 330 lb-ft

Typical 6.5 turbo = 215 hp / 440 lb-ft

If they'll get 20 mpg in a 4wd Suburban I think they'll do that well in an AWD Astro no problem, which is an improvement of 3mpg, highway.
.
A guy on the astro safari forums made this exact swap (4.3 -> 6.5) in 12 days.
.
Here's a video

 

[Stroverlander]

3 mpg increase wouldn't be nearly enough to offset the increased cost of diesel fuel, nor the expense of swap.

For sake of accurate Astro engine specification, early Gen I vans were 165 hp / 235 lb ft torque while later Gen I and Gen II ('97-up) are 190-200 hp / 250-260 lb ft torque.

What does that 6.5L diesel weigh vs stock? Couple hundred pounds more, at least?

If you want to do it, go for it, I enjoy reading a good build thread.

 

[ihatemybike]

I've always loved the idea of a diesel swap in an Astro, but I've never had a 4.3 die since I started doing the majority of my vehicle repairs for me to really pursue the swap. I'm also able to regularly keep my MPGs hovering around 20.

Currently the engines I'd most like to try stuffing in are the Navistar MaxxForce 5, Mercedes-Benz OM642, and VM Motori 630T.

Main diesel draw for me is veggie oil burning.

 

[Mwilliamshs]

...Typical 6.5 turbo = 215 hp / 440 lb-ft...

For sake of accurate Astro engine specification, early Gen I vans were 165 hp / 235 lb ft torque while later Gen I and Gen II ('97-up) are 190-200 hp / 250-260 lb ft torque...

...Currently the engines I'd most like to try stuffing in are the Navistar MaxxForce 5....

The VT275 (Maxxforce 5, 4.5 v6, basically the 6.0 v8 with 2 cylinders cut off) was rated at 200hp and 440 lb-ft. Good little engines in my experience (cab overs) but the compound turbo setups were junk from the word go. Most got replaced under 100k miles which doesn't matter much as packaging 2 turbos in an Astro would be a nightmare. Runing veg oil an original ULSD engine would be a lot more work than an older IDI, especially one with mechanical controls like a pre-94 6.5/6.2.