454 swap

[josh25]

Ok here is the deal I have contemplated swapping a diesel into my 95 suburban however I think I will try to do a 454 swap instead. I have found a complete 99 454 with about 120k miles on it here in town for $800. I have the stock 4l60e tranny, what is you guy's thoughts on doing a shift kit on my tranny for that 454? What sort of problems am I facing with doing this swap as far as what other parts are recommended for me to swap. That engine does have the computer. I want to do this swap since I'm stuck with my suburban I want to make it a better at towing and I believe my 350 is on it's last leg with a 180k on it. I also only get 10-11 mpg with my 350 so I'm hopping that with the newer 454 I may get a little better fuel economy as well as more power. Let me know your feed back.

Josh

[daved931]

I wouldn't expect a lot better fuel economy with a 454. You'll definitely get more power. I don't know about swapping in a 120,000 mile engine. Do you think you'll have an opportunity to freshen the 454 up before dropping it in? It seems like, if you're going to go through the trouble of making the swap, a newer engine would be nice.

If you're going to tow with a 454, the 4L60 probably won't hold up, even with a shift kit. Sooner or later, that sun shell gear will come apart and waste that whole transmission. Try to get the 4L80E and cross member from the donor.

[m grasso]

we just got done putting a 7.4 in my buddys truck, that mofo burns tire all the way through 4th.... that is untill the tranny sead phffffff! you should look into beefing up yours so this doesnt happen to you. as far as gas milege its about the same as the 350 when ur out of the peadle. im puttin one in my truck found one in the junk yard for $400, its gonna be nutts in my little ol stepside! good luck and have fun!

[josh25]

I'm going to go and try and take a look at that 99 tomorrow. It's a tough decision trying to decide on rebuilding my worn out 350 or upgrading to the 454. Seems like in my opinion upgrading to the larger engine would be a pretty good idea doing that and adding some rear air bags would make it a more capable tow vehicle. I know I can't get any worse than my 11 mpg city and 13 mpg highway that i'm currently getting.

[daved931]

I'm going to go and try and take a look at that 99 tomorrow. It's a tough decision trying to decide on rebuilding my worn out 350 or upgrading to the 454. Seems like in my opinion upgrading to the larger engine would be a pretty good idea doing that and adding some rear air bags would make it a more capable tow vehicle. I know I can't get any worse than my 11 mpg city and 13 mpg highway that i'm currently getting.

I think the upgrade to a big block is a great idea. Especially since GM did all the R&D to make it all fit.

I really would look into taking the 4L80 out of the donor though.

[josh25]

I went to town and was talking with a mechanic and he was telling me from what I described about my truck that I may have more of a tranny issue than a worn out motor problem. I'm really torn here on what to do mainly because of $. If my motor is good I was thinking I can upgrade the tranny maybe put a 4l80e, headers, cam, intake. Would those things be benefical to gain towing power and fuel economy what suggestions do you guys have with that. I hear that there is quite a bit of things that can be done with these 350's such as upgrading to vortec heads but I'm unsure on what all I would need to do that and cost.