I need some very basic information. What are the differences between the 1989 - 1993 12 valve engines and the 1994 - 1998 12 valve engines?

 

89 - 91.5 larger injectors non intercooled...91.5-93 small injectors lower boost diff turbo turbine housings 94-98 p7100 injector pump(the bomb) turbo some miner things thats to start with. any one else ?the p7100 makes big power

 

So, 1994 - 1998 is the desired engine?

 

i think so thats what i would get 98.5 you start getting it to electronics and 24 valves

 

I just started looking for a new project. I do not want an electronic engine so I am staying away from 1998.5 and later. I've seen that Dodges are always divided at 1989 - 1993 and 1994 - 1998, but I was unsure of the differences or the advantages of one over the other. Thanx for the information.

 

no problem that what we are here for

 

A couple of bargaining points for you, not necessarily a reason to avoid'em.....

89-91.5 autos have irreplaceable 3:07 gearing.
94 auto's are specific to 94. Transfer cases on 4x4's are not interchangeable with other years. This will be a consideration if your core is not buildable if it ever disintegrates.

 

redleg what do you mean when you say the early ones have irreplacable 3.07 gearing ?
i have a 90 model 250 with that gear and the 727 ? auto , i need to upgrade the trans so it will handle a little more power .

 

If you're looking at a second gen truck try to find a 97.5 - 98.5 model. They have most of the bugs worked out and they are the one's with the better of the P-Pumps.

pb....

 

i dont know what axel that year has, but it may just need a different carrier in order to get deaper gears. if its a 60 or a 70 (which it should be) you should be all set. i just forget teh carrier breaks off hand. jiMMy

 

Pre inner-cooled trucks are also pre over-drive. The autos were geared with 3:07 axles. Dana 70 rear, 61 in the front. 61 is a 60 that has been modified for the dimensions needed for the 3:07 in that size of a carrier. The 70 is also modified to accept the 3:07, don't know why they didn't name it a 71 though. Dana no longer offers 3:07 gears to replace them if they brake. The housing AND carriers are specific to the 3:07 and the housing needs to be modified to accept lower gearing. If need be, Ford used a 61 in delivery vans a while. You could swap the 70 if damaged for a Ford 61 in a SRW configuration. I'm pretty sure the internals couldn't be swapped though. Also the 70 axles are 32 spline. Not sure if they are still available, or could be custom made. Luckily my old ones weren't damaged, so I have spares now. Yes many salvage yards are aware ofthe rareity of the axle.

 

Aren't the blocks different between the 1st and 2nd gen 12v's? I thought the 94-98.5 were made to reduce noise or something. Maybe it's just something I've heard I dunno.

 

3rd gens are reduced noice from the common rail system. 1st gen heads have to be worked on to accept the 2nd gen pump, and 2nd gens are suppose to flow a little better. Also, on the 1st gen the water port is a little restrctive around #1 and can trap air and cause cooling issues.

 

so redleg , what you are saying in essence is ...............take care of that rear axle ( mine is 2wd ) as you can hardly find replacement parts .

thanks for the info

 

Yes, changing the fluid now will give you the excuse to go in and look at the carrier. Make sure the guide pin in the spider assembly is not wearing out the holes it rides in, if the rear clunks at all, check for them to be real sloppy or egg-shaped. Also make sure the lock pin that secures this to the carrier is in good shape, you might pull it and apply some locktight. For best insurance I think you can get both pins for under $50, and replace them anyway. I intend on doing that when the weather breaks. Worse case scenario, if your holes are getting egg shaped, you should be able to get another carrier and have it machined to spec, but you can't get new gears. I probably would have just went with a 3:54, but I have 4wd. Don't have any problem with the performance of the 3:07 either.