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quick noob questions

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rxm6

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Just acquired a 75 and after thoroughly burning myself out on internet research, I turn to you guys with a few questions.

1. Just want to verify that for road use, at stock height, I can use 33x12.50 without trimming. I have found at least a dozen pictures of 73-75 blazers with 33x12.50 that are stock height and appear to have not been trimmed, but I prefer safe rather than sorry.

2. The blazer has after-market mufflers and the tail pipes come out on both sides of the truck just aft of the rear tires. The pipes are approximately two inches in diameter and are pointed downwards like stock exhaust pipes from the era. Also, the PO tells me that was how the truck came stock. The only reason I question this is because my 90 has both pipes coming out to the right side. So, is that stock tail pipe arrangement on 75's?

3. The emblems that sit near the mirrors on the front fender have gone missing and, after paint, I would like to put on some new ones. Is this something I can get reproductions of or will I be going to the junkyard?

4. Just for future reference: The windshield has the radio antenna embedded in the glass. Is this something that they still make, or will I have to look for other options when replacing the windshield?

Thanks for any help.
 
rxm6 said:
Just acquired a 75 and after thoroughly burning myself out on internet research, I turn to you guys with a few questions.

1. Just want to verify that for road use, at stock height, I can use 33x12.50 without trimming. I have found at least a dozen pictures of 73-75 blazers with 33x12.50 that are stock height and appear to have not been trimmed, but I prefer safe rather than sorry.

2. The blazer has after-market mufflers and the tail pipes come out on both sides of the truck just aft of the rear tires. The pipes are approximately two inches in diameter and are pointed downwards like stock exhaust pipes from the era. Also, the PO tells me that was how the truck came stock. The only reason I question this is because my 90 has both pipes coming out to the right side. So, is that stock tail pipe arrangement on 75's?

3. The emblems that sit near the mirrors on the front fender have gone missing and, after paint, I would like to put on some new ones. Is this something I can get reproductions of or will I be going to the junkyard?

4. Just for future reference: The windshield has the radio antenna embedded in the glass. Is this something that they still make, or will I have to look for other options when replacing the windshield?

Thanks for any help.
Click to expand...

1. Depends on if the springs are sagging, but you should be fine on the street.

2. No clue on the stock configuration

3. I would try LMC Truck (mentioned above) or classicparts.com

4. I had my windshield (w/embedded antenna) replaced by a local shop, he said he keeps one on hand b/c so many truck have them.

hope this helps and welcome to the site!
 
1. As stated, it depends on the springs. It also depends a lot on the backspacing and width of the wheels. If you run 8 inch wheels with less than 4 inches of backspacing, you can probably do it, although if you end up even mildly flexed for any reason and slightly turned, the tires will catch the back-bottom edge of the front fenders, potentially quite seriously with 33's.

2. '75 is pre-catalytic converter I think, so it may have been true dual pipes down either side of the truck from the factory. The reason they all went to one-sided setups from the factory was to run through one cat because cats are expensive.

3. LMC Truck, as stated by others. It's my guess that if you wanted to spend 100 times what the truck would end up being worth, you could buy a frame and build a brand new Chevy truck from LMC! :) Meaning they have just about everything.

4. I've had several in-the-glass-antenna windshields replaced over the years on an assortment of GM cars and trucks and never had a problem finding them. The worse-case scenario is you'll have to wait a few days for a shop to special order one.
 
I can answer a couple of those:

3. No the emblems are not available for the early design (pre-81) where they are mounted above the body line. LMC carries the versions for 81-up, but the early version hasn't been made available. I found mine on e-bay and paid, I think, about $50 for a very nice NOS set. No place I have found carries the early version in stock and if you are painting, I would look for the best quality that you can find. Worst case scenario you can always touch up some emblems with enamel.

4. I just had my windshield replaced in March, and aside from the cost being higher than it would have been without that antenna, they had no issue delivering the new glass the next day. SAFlite still makes them, and usually has them in stock. Other manufacturers may also make them, and may stock them, just call around.
 
Throwing in my two cents,

1. As Desert Yeti previously stated it all has to do with wheel size and back spacing and flexing. Also a big factor is the type of tire as not all 33's are the same. My dad has an 86 SB with 33 Matercraft MT's on factory rallys and the only rubbing he has is one of the steering joints on the pitman arm.
3.Emblems for that era are only available on Ebay. If you do find some that are so-so, you can take metal polish and 0000 steel wool and polish-em up good. On mine that I got I striped the old paint with nail polish remover and taped off an repainted them. (20 hours per emblem) took less time to intall my lift and tires.
 
Thanks for all your help, really appreciate it. I'm still pretty confused on tire size though and a bit bummed out about the fender emblem. Anyway, thought I'd post some pictures and maybe get a thumbs up or down on the 33's, but I can't :(, so I put some in my album. Stock suspension doesn't seem to flexy and I doubt the pictures of tires shoved deep inside the wheel well will be me.

Btw, BIOHZDK5 mentioned that 33's are different, if it helps, I planned on using bf goodrich all terrain t/a's
 
It is all a fit and see type thing. THey may fit one guys truck, but not anothers of the same year and setup.
 
judging by you pics, looks like you got some pretty tired springs!!! 33 BFGs are wide on the tread width. my 75 had 31's on it and they fill up the well! They may go on there but probably gonna rub all over th place. You may be able to get away with a body lift to make em fit. Here is what I am running

RC 4"springs front/4" blocks with 2"AAL rear with 33x12.50x15 TSL SS

IMG00102.jpg
 
BIOHZDK5 said:
judging by you pics, looks like you got some pretty tired springs!!! 33 BFGs are wide on the tread width. my 75 had 31's on it and they fill up the well! They may go on there but probably gonna rub all over th place. You may be able to get away with a body lift to make em fit. Here is what I am running

RC 4"springs front/4" blocks with 2"AAL rear with 33x12.50x15 TSL SS
Click to expand...

Yeah, well, sitting in a garage for 15 years will do that to springs, but honestly, i think that it is close to stock height. It doesn't sit much lower than my dad's 90. I may just end up running 31's for now because I'm more interested in restoring it first. Thanks for all the help though, I appreciate it.
 
I may have some input on question 2. I think that '74 was the year that cats became mandatory for cars. I think trucks had to have them a couple of years later, but I'm not sure when. I once drove a '74 CJ-5 (which the EPA condsidered a light truck), and it had the original dual short pipes with little mufflers that came right off the headers and exited in front of the rear tires. I don't think any Blazers ever had dual exhaust from the factory, but anything's possible. It could have been a special order. On trucks and Blazers from the '80s and '90s, it may look like they have dual exhaust exiting on the same side with the two pipes close together, but if you look up under them you'll see that both tail pipes come out of one muffler. I have no idea why they did that.

As for the 33s on the stock ride height, it could work. I had 33s on my '85 truck when it was stock height and they didn't rub, but they were worn out off-brands. Maybe you could borrow a set from someone and put them on and drive around just to test them out, or at least measure a set of the tires you want after they're mounted on a wheel and aired up to see if they might fit. That might be a pain. Don't worry about trimming the fenders though. They probably have some rust that needs cutting off in that area anyway. The truck will look better after you do it. You'll feel bad at first, but I guarantee you'll like being able to run the larger tires without spending a lot of money on new springs.
 
andyblack said:
I may have some input on question 2. I think that '74 was the year that cats became mandatory for cars. I think trucks had to have them a couple of years later, but I'm not sure when. I once drove a '74 CJ-5 (which the EPA condsidered a light truck), and it had the original dual short pipes with little mufflers that came right off the headers and exited in front of the rear tires. I don't think any Blazers ever had dual exhaust from the factory, but anything's possible. It could have been a special order. On trucks and Blazers from the '80s and '90s, it may look like they have dual exhaust exiting on the same side with the two pipes close together, but if you look up under them you'll see that both tail pipes come out of one muffler. I have no idea why they did that.
Click to expand...

I actually just found an old picture of a stock 75 k5 and it does have dual exhaust on either side. On the other hand, I've found an old picture of another stock 75 and it only has one outlet on the driver side. I wonder if the exhaust was dependent on the factory it was made or perhaps an option? Either way, I think I'll just keep it and accept it as the stock configuration.

andyblack said:
As for the 33s on the stock ride height, it could work. I had 33s on my '85 truck when it was stock height and they didn't rub, but they were worn out off-brands. Maybe you could borrow a set from someone and put them on and drive around just to test them out, or at least measure a set of the tires you want after they're mounted on a wheel and aired up to see if they might fit. That might be a pain. Don't worry about trimming the fenders though. They probably have some rust that needs cutting off in that area anyway. The truck will look better after you do it. You'll feel bad at first, but I guarantee you'll like being able to run the larger tires without spending a lot of money on new springs.
Click to expand...

We put 33's safely on my dad's 90 blazer, but the 90 sits a good 3 inches higher than the 75, most likely due to a body lift or something, either way, that's how it came from the factory. I did some more measuring as well and my wheel wells are 34'' across in the middle and 36'' across at the bottom. So, if I was driving straight I would be okay, but I think I would hit the fender when turning because of how the wheel moves back and forward when turning instead of just rotating on its axis.
 
Dual pipes was part of the high output package. It was always an option. In the 80's when the 6.2L diesel came out they took the same dual exhaust design and made it standard on the diesel K5's.

33's. Well, as stated above there's a lot of things to consider.
-Your springs might be sagged down and that makes your task more difficult. Could just be bushings though. Lots of folks on here have replaced the bushings in their springs and shackles and noted an increase in ride height.
-Also as noted true height differs between tire makers and tire designs. Some makers are infamous for having 33's that somehow turn out to be 31's when under the weight of a truck. Others are actually taller than 33" and end up being close to 33" when under the weight of a truck. Width is similar.
-Also consider rim width and backspacing. If you put the 33's on 15x8's with 4" of backspacing like the factory 15x8 Rally's than you could probably make them fit a lot easier than if they were on 15x10's with 3-3.5" of backspacing. Wider rims and less backspacing will for sure push them into the fenders.
-Don't be afraid to trim. A little nibble here and there, tastefully done, and you won't even notice it's been done and you gain a lot of clearance. Not to mention there's lots of unnecessary metal down there at the corners of the fenders.
-Relocate your front axle forward an inch or so. www.OffRoadDesign.com has their zero rates for this. The front axles in these trucks are not centered in the front wheel well. They're back towards the rear of the fender an inch(ish) and this is why that's always where the tire rubs when you turn or compress the front. The tire swings back and up and crunch meets the sheet metal.

I've seen 35's on a stock truck with a 30 year old sagged suspension. Michigan rust made it possible but still, you could do it to a pristine truck as well. Would just require metal work and time.
 
How will using the zero rate to move the axle forward one inch affect the front driveshaft though? Will it have to be lengthened? That could cost more than a lift would. What about the steering, too? Would the extra inch forward mess with that? I've never used one of those zero rates, but they sound like a good idea.
 
The driveshaft SHOULD work. You should have the extra length necessary, especially if the 1" of the zero rate is all you have for lift. With taller lifts you might not have enough.

Steering is fixed by shortening each drag link half the amount you moved the front axle forward. Adds a bit of bump steer but most have reported it's minor. Not like these things steer that great anyways with the stock steering.
 
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