What TBI year to buy and why????

[RAINS]

Going to be shopping for a full size blazer shortly I hope. I have a few questions though. This will be my primary ride so the tires are going to be no bigger than 31's. But eventually I might put 33's on. I'm mostly trying to get a ride that can haul 3-4 guys down bumpy rocky desert roads and mountain snow. I do forsee the addition of a winch and maybe a rear locker a few years later. I've also had issues with carbed rides before. In a day of exploring I can easily drive up above 6k feet from sea level. So I was thinking about a later TBI blazer. But will a 10-bolt rear hold up? Or should I be looking at replacing at least the rear when I put a locker in it? Any suggestions would be appreciated. I look forward to learning a lot from this forum. Thanks!


R

 

[Emmettology 101]

Welcome!!!


My choice would be a 90-91. Bascially the newest K5/Jimmy you could find in your price range....

As far as the 10bolt is concerned, I think you would be fine even with 33's.... But you could always find a 6 lug 14SF to bolt in when you go to a locker.

 

[dyeager535]

Usage of the 10 bolt really depends on you. The truck you end up buying has had a 10 bolt in it for how many years now?

Honestly, even the gov-lock 10 bolts are ok (G80 on the glove box RPO sticker)
IF you aren't bad with the throttle. If you really just use it to drive around, explore, etc., then 10 bolts will probably be absolutely fine for you. I've had a Blazer (one of two anyways) for 10 years now, and this year is the first time I EVER broke one, and that was on the street after installing a new engine and being hard on the truck.

I'm running 33's on my truck, don't think I'd have it any other way at this point, and if it weren't for me liking to mash the pedal fairly often, the 10 bolt would have held up fine.

I agree with going '90-91. On top of everything being newer in general, the electronic speedometer those years is a plus in my opinion. Especially if planning on bigger tires later, speedometer correction is easier with the electronic speedometer. As with anything, the longer a vehicle has been out, the more refined its various components get. I wouldn't complain about any of the TBI trucks, but if I had the choice between an "identical" '87 and '91, it would be an easy choice.

 

[Zeitler]

the engines was improved

1989:

The L05 5.7-liter V-8 now had serpentine accessory drive belts in place of the older multi-belt accessory drive.

1990:

The 5.7-liter V-8 (L05) engine was improved for 1990 with the addition of improved oil control rings, a redesigned rear crankshaft seal, a new camshaft sprocket design, non-asbestos intake manifold gaskets, and heavy-duty intake valves.

The Blazer body also used double sided, galvanized exterior sheet metal

(i wonder how much this helps against rust??)


1991:

The TBI (throttle body injection) system used on the Blazer's standard 5.7-liter V-8 had longer throttle shaft bearings, new throttle return springs, and improved fuel mixture distribution. The 5.7-liter V-8 also had new heavy-duty intake valves and powdered metal camshaft sprockets.

Standard on all engines was a lighter more powerful 100-amp CS130 alternator.

 

[Thunder]

89-91 IMHO Are the best of the TBIs.
reasons:
30 spline axles
NP 241 Xfer case. able to shift in and out of 4x4 Hi on the fly.
700R4 trans has all the upgrades earlier models dont have.
Cool loking grill.

10 bolts should be fine for your uses. Either look for a gov lock or If you get an open rear just put in a lockrite. Try to get one with a 3.73 or 4.10 gear ratio if you are planning on getting 33" tires.

I have a 89 with 10 bolts 33s and lockrites I use my K5 hard. I go thru U joints regularly and I brokesome pins in my lockrite last winter towing out a Jeep in deep snow on a snow wheeling adventure. But my ten bolts are holding up just fine. (Knock on wood LOL)

 

[Jonny-K5]

89-91 IMHO Are the best of the TBIs.
reasons:
30 spline axles
NP 241 Xfer case. able to shift in and out of 4x4 Hi on the fly.
700R4 trans has all the upgrades earlier models dont have.
Cool loking grill.

10 bolts should be fine for your uses. Either look for a gov lock or If you get an open rear just put in a lockrite. Try to get one with a 3.73 or 4.10 gear ratio if you are planning on getting 33" tires.

I have a 89 with 10 bolts 33s and lockrites I use my K5 hard. I go thru U joints regularly and I brokesome pins in my lockrite last winter towing out a Jeep in deep snow on a snow wheeling adventure. But my ten bolts are holding up just fine. (Knock on wood LOL)

i agree 100%.
i've got an 89, i think they are the best year, but 90 or 91 are good choices too.try and find one that hasnt been used for towing, one owner would be good. kept good maint. records is always a plus. 4.10 would be perfect, but hard to find. alot easier to find 3.73, they are still decent w/ 31's. pushing it a bit w/ 33's.

 

[RAINS]

Thanks guys I will keep my eyes open for a 90-91 that has not been used to tow. I've seen 87's amd 88's with under 10K on motor and tranny rebulds for 2800-3800 and some under 90K 90's and 91's for around 4K. Do you guys think a low milllage blazer is best or one with a rebuilt motor and tranny?


R

 

[dyeager535]

I personally would say low mileage, UNLESS there are some qualifications on the engine/transmission that can be proved.

The only time I'd consider an engine/trans to be exactly what is advertised (and worth paying more for) if the receipts exist showing it's a GM engine/transmission installed by a GM dealer. It is way too easy to lie about what an engine is, or how it was built, or how many miles are on it.

At least when/if you need to put either one of those in a lower mileaged truck, you will know what is in it. No reason to pay for other peoples mistakes any more than you have to.

 

[RAINS]

Good point there really is no way to tell if and when a motor/tranny has been rebuilt. "Yep it was rebuit a hundred miles ago and was only driven to church on Sunday by a little old lady."


R