Hopefully someone here can help me on this one.

The 4.3L VORTEC engine seized in my 1995 GMC Jimmy SLS. I've heard from everyone that I've talked to that the 4.3L VORTEC in that year of Jimmy can only be replaced by the exact same year and model. I know there are hundreds of 4.3L VORTEC's out there, but very few 1995 ones. The ones I have found are priced extremely high compared to all the other years, even newer motors with less miles on them!

Can I replace this motor with any other 4.3L VORTEC out there? If so, what ones? Does anyone out there have one around they no longer need? HELP!!!

The 4.3L VORTEC I have is the top mounted distributor, located right behind the intake manifold.

Thanks in advance.
Jim

I talked to the parts guy at the shop (GM dealership). He says the blocks are the same, so as long as you switch everything over (like the intake and the oil pan, along with all the accessories) you should be fine.

Clay

Thank you for the advice. The Chilton book I have for this says nothing about differences in motors. By the looks of things, it's going to be "fun" pulling it out of the compartment.

Thanks again and if anyone has any insights to pulling the motor out of a 1995 Jimmy, by all means post a way! For that matter, any suggestions for add on improvements while I have it out.

Jim

Remove the radiator completely.

Replace the CPI unit as part of the rebuild.

Headers are available, and to help.

Steer clear of reusable cloth/oil air filters.

Clay

I want to thank you again for your advice. I thought I would post an update on things.

Since I first posted, I've done a ton of further research into what block, (for either a "W" or "Z" VIN) will work with the 1995 Jimmy. Mine is a "W" VIN and here is what I've been told by several different dealers, junk yards, etc....

1. Any 93 - 98 "W" VIN long block will work, but you need to make sure that if you have a cam vibration dampener in the dead block, the newer long block you're going to use must have one as well. If not, you will have to remove your heads and replace the heads on the newer engine.

2. On some "W" VIN long blocks the bolts for the intake manifold mount straight down, others mount at an angle. You need to make sure you match this or you will have to switch the heads out.

3. You can't use a "W" VIN long block that uses the intake manifold with the throttle body on the top (I believe they call this a TDI?) if your bad block has the intake manifold with the throttle body in the front.

4. A "Z" VIN engine from 93 & 94 will work, just swap out all the other parts.

5. If you have a steel oil pan on your old block, the new block you're using must have one as well. Some "W" VIN's came with an aluminum oil pan and that engine can't be swapped out with a steel pan.

6. If your old block has a distributor with side fitted spark plug wires, then your new engine must have used the same type. You can't swap out a top fitted distributor with a side fitted.


So there is no wonder why no one knows what can fit what "W" or "Z" VIN engine block with all this conflicting information. Basically I'm back to where I started months ago, just more confused. Some dealers told me that from year to year the engine block numbers were the same, others told me they were not. Geeezzzzzzzzz.... Give me the old days where any 350 slid in and ran.

Can anyone validate or disprove any of the information above? I don't want to purchase a long block only to find out that it won't work because of some crank sensor was added or vibration dampener isn't on this or that engine.

I am very willing to share all of the information I gather and to post all pictures and description of the swapout on here to help others in the future.

Thank you in advance.

Ah, yes. The early Vortec blues. '95 was a rough year for GM trucks. The early ones were OBDI, some of the later ones were OBDII. The intake bolt angle you are refering to (angled or straight) refer to the four inside ones, not the bolts on both sides of the cooling ports. They did the same thing on the V8's. I had a friend in Illinois who had a Suburban with Vortec heads (center bolted valve covers), the center intake bolts were angled, and it had a feedback Q-Jet on it(!). Messed up.

So which distributor did you say you had? The reason I ask in that the flat cap is the type used with a crank sensor, the vertical cap is not. So you could run your old distributor on a newer engine if you just plugged the crank sensor hole in the timing cover. You would have to make a timing indicator for it, though, since the newer style is timed with a scan tool reading the CMP Retard instead of using a timing light. All other things being the same, you could run a newer block than yours, just replace the lower intake with the one to match the heads for the bolt angles. It may be cheaper the get the more common engine with a lower intake than to try to find your specific application. To see what will work, compare part numbers for your engine to the newer and hopefully cheaper engine you want to use. Check numbers like upper intake plenum and CPI unit. If they match, chances are you will be ok. You will most likely need to use the EGR for the newer engine, as they are calibrated to the cam, and if the variation is enough, you will end up with a P1404, EGR Pintle Position code.

Definately go with the headers, they will make a huge difference. But don't get cheap ones. You know how hard it is to get that #4 plug with the steering shaft in the way? Imagine a poorly designed header tube...

If you have a friendly shop in your area, see if they will let you sit down at their Alldata computer and just browse. The Parts and Labor section lists factory part numbers you could use for comparison. I'm a 20 year ASE Master, unfortunately I don't spent much time of this forum, so would be little help. But a box of donuts should get you all the time you need with a shop computer to figure this out. Good luck!

I have about 6 different spark plug tools to get that one plug out and none fo them work very well <img src="/forums/images/graemlins/angry.gif" alt="" /> Typical GM. <img src="/forums/images/graemlins/rolleyes.gif" alt="" />

I was watching TRUCKS the other day on Spike TV and they replaced a 4.3L with a 350 small block. It looked fairly straight forward, but that was tv and not my garage.

Any thoughts from anyone on trying this on a 95' 4x4 Jimmy?

I'm sure there is a ton of other issues I'll have to deal with like steering box, front axle, etc...

contact advance adapters or type it in on your puter they have complete conversion kits for a 4.3 to a 350 swap and its easier then you think to do the swap
both are 90 degree blocks all that really needs to be done is change motor mounts, remote oil filter kit, different radiator and cooling fan, a adapter plate for tranny depends on which tranny you have
i have done 2 s-10's both were 2-wheel drive and you talk about fun ! lol no speeding tickets yet !