Have a 99 ram van 1500 with the big ole 5.9l v8. I may have a blown head gasket and am thinking about an engine swap.

I don’t need the van to tow like I used to so I am wondering if I can swap for a smaller engine like the 3.9 v6 (or the 5.2 which seems more common). I would prefer the 3.9 because of gas prices, but I think I saw somewhere that it requires the 3.55 axle ratio and I believe I have the 3.92.

Is that true? And I suppose it would be a big job to change it? (I know nothing about changing any of that).

Thx in advance

Also, seems like the 5.2l would be a straight swap I hope?

 

I don't think you would like the 3.9 in your brick.. erm, Van.... It just doesn't have the power to move all that weight. I am also not sure how much of a gas mileage increase you would see going down in engine size... might not change at all with the 3.9, as you will be working that engine HARD..... I think you would be further ahead just rebuilding what ya got. Save some money, and spend it on the little bit more gas you burn.

 

Thanks HeyYou, I would prefer to do a rebuild, my concern is doesn’t the coolant do internal damage? The van has been like this for a long time, like 5 years I think. I just rarely used it so I would replace coolant when it got too hot.

I worry a rebuild won’t catch all the damage. Though I’m not sure what would get damaged anyway.

I’m bringing it to a mechanic because this is beyond my skill set. What should I ask them to look at to see if the coolant damaged anything?

Also, the 5.2 would be enough, right? I see more of those for sale than the 5.9s?

Thanks again.

Yea she’s a brick but she’s my brick lol

 

If you didn't get coolant into the oil, then no real worries. The stock heads are notorious for cracking though, and if it got hot, you can be quite sure they are. Odessa/Clearwater cylinder head service out of Florida off NEW castings, with thicker decks, to avoid that issue. It's generally a better idea than trying to rescue the stock heads, as part of that, is machining the deck, which makes it even thinner..... not a good idea. Can probably get away with doing the top end, and get another couple hundred thousand miles out of it.

 

Ok thanks, unfortunately I’m not in Fla anymore. New Mexico by Las Cruces/El Paso. Anywhere I can get a new head here? Rather pick it up than ship it.

 

The 3.9 gets about 13 MPG on a good day. It is also shorter than the 5.8 and requires an ECM for a 6 cylinder instead of an 8. Finally, the vans that came with the 3.9 had 3spd tranny, no OD, simply because it was too much gear for the engine to push. Considering the low MPG gain, if any, and all of the headaches to swap to a 3.9 IMO it is not worth it.

 

Get the casting number (not just make, model, year) off the head and do a search on eBay for it. A couple of years back I got a reconditioned head for a few hundred bucks. Some want you to ship you head back some don't, so take a good look around at a few of the listings.

 

Drain your engine oil after the van has sat a couple days, or just quick pull the plug and put it back in, any coolant/water that could've gotten into the oil will be on the bottom. If you get oil right away you're good to go and I would just do a top end. If you do get some coolant right away. I'd rebuild the top end change the oil and go

Newer engines glycol in coolant can affect the bearing coatings but something of these vintage I wouldn't worry a bit about coolant in the oil, provided you address the source of it. Wouldn't hurt to run a compression test on the motor before you tear it down, you could gauge how "tired" the engine is but a head gasket job is alot cheaper then a rebuild if the bottom end is solid

 

Coolant in the oil dramatically reduces it's lubrication properties, and will smoke rod and main bearings pretty quick..... If the oil is contaminated, change the bearings......

 

agreed