Engine Choice Please Educate Me

[marvelousmarvyd]

I have a 1998 two door chevy tahoe that I'm looking to replace the engine and transmission sometime in the near future. i'm trying to decide whether to go with the 5.7 or 5.3, what are the pluses and minuses of each. I would like to get better performance and decent mileage from the engine that is recommend because the truck will be used for ordinary everyday driving. Please also provide some idea as to where one might be able to find a shop for the engine that is recommend. Thanks and sorry for all the newbie questions.

 

[lesterl]

Why are you replacing the drivetrain?

Are you gonna install an all new computer system and wiring harness (custom computer tune would probably be in order as well.)?

I think the 5.7l has more low end grunt than the 5.3l, but the 5.3l seems (at least as far as the few of each I have had) to wind up faster and have more top end power.

I guess it depends upon why you want to swap and what you want to do... More info please.....

 

[marvelousmarvyd]

The truck currently has 170,00 miles on it, sooner or later I know the engine will have to be replaced, at the same time i would also like to do the tranny. The truck was not taken care of by the previous owner from what I can tell. I know it will have to have the exhaust system replaced from what I've been told so far, I'm already looking into a dual exhaust. I have no problem with replacing the electronics also if I go with the 5.3, I bought the truck knowing that I would be doing a restification at some point. I,m just curious which engine would give me the better mileage, performance, and reliability. The truck will be a normal everyday driver with a few cross country trips taken each year. By the way thanks for the reply, I appreciate all the help I can get on this future project. This has always been my dream truck to own and I'm looking forward to personalizing it to my taste. One last thing is that I'm hoping to get at least 20mpg whichever direction I go as far as the engine.

 

[lesterl]

I had a 5.7l Z71 Extended cab pickup that I could get near 20 on a long hwy trip. Also had a 99 5.3l Z71 Ex cab P/U that was about the same.

Any engine can be tuned, I personally would go with the 5.7l as I would think they would be cheaper to build up to what you want and possible more aftermarket goodies vs the 5.3l..... Just saying......

 

[marvelousmarvyd]

Thanks lesterl, i forgot to mention that I do need to keep cost down and your suggestion on the 5.7 makes sense. From what I've been reading on this forum a 5.7 will run anywhere from $4000 to 5000 installation included. Will have to check around here in Vegas to see what the prices are like. If anyone can recommend a source out my way that I should consider please feel free to comment.

 

[lesterl]

Why not just rebuild the 350 thats in the rig now? They can be real cheap to go through if you dont buy every little thing..... I went through an 89 2.5l with fuel pump for $200 and if I had spent the extra money to replace the leaky radiator I would still have it.

 

[marvelousmarvyd]

That's an idea that I haven't really considered, I know there are rebuild kits out there I will have to look into that.

 

[lesterl]

I tore my 2.5 down, honed the cylinders, new rings, new main and rod bearings, gaskets, etc, and a fuel pump like I said, it was around $200...... If a v8 could be done for $400 that aint bad.... Definitely look into it, it can be kinda fun... Just make shure you get the specs and follow a teardown/ assembly manual so you do it right....

 

[marvelousmarvyd]

lesterl,

Thank for the info, unfortunately I haven't done any major engine work myself in almost 30 years. I'm now retired and will be farming the work out this is why I asked if there is anyone who is familiar with the shops in Las Vegas could recommend a couple out here that are reputable for me to look into. I am going to try and do some of the small stuff maintenance wise, but as far as pulling the engine the last time I've done that was back in 1986 when I was a mustang fanantic.