The GMT400 thread (88-98 GM full-size trucks)

Daily driver 1994 GMC Sierra SLE.  350/4L60E/3.42 gears.  Was a trade-in at my old dealership in 2009 with 131k miles.  Currently has 215k.  It's squatting here due to a full truckbox and a hydraulic press in the bed.

Has 2" drop shackles.  Impala SS wheels with 245/70R17 tires.  3" mandrel bent exhaust.  Pacesetter shorty headers, junkyard edelbrock performer TBI intake, ultimate TBI mods, underdrive crank pulley and a volant cold air intake.  Burned a chip with a modified fuel map.  Modified the VSSB for the 30.5" tires and installed sealed beam headlamps from a 88-90 truck.  I have almost everything to perform a 2/4 drop minus the shocks.  Maybe switch to a 275/55R17 tire.  Long term a 5.3 swap.

Got a pic of mine this morning while I had it warming up for a recycling run. 

My 98 Suburban, huge regret selling this one. Don't have any pics of my 90 RCLB c1500.

So hope it's cool if I ask a Gmt400 question in this thread. 
 

looking for speakers to fit in the factory dash and the factory spot on the b pillar. They look funky and I didn't have much luck on the webs for cheap replacements. 
 

also any one got a line on manual window interior door arm rest pads? My drivers is toast and all I've found on the web is pricey new ones. Facebook market place and Craigslist have been no help as it seems most have power windows. 

Speakers are 4x6, but ive had good luck with 3.5 in the rear openings,  and adding 6.5 to the doors. 

rattfink81 said:

Got a pic of mine this morning while I had it warming up for a recycling run. 

There’s a good, straight, honest truck.  Hold on to that.

In reply to A 401 CJ :

Thanks, It looks way better in photos then person but it's solid and I bought it cheap so it's a keeper. 

'97 GMC with the gutless 305. Stock as stock can be. It's grandad's old truck, though, so I plan on holding on to it. I'm taking it on a 1500 mile drive literally tomorrow.

rattfink81 said:

So hope it's cool if I ask a Gmt400 question in this thread. 
 

looking for speakers to fit in the factory dash and the factory spot on the b pillar. They look funky and I didn't have much luck on the webs for cheap replacements. 
 

also any one got a line on manual window interior door arm rest pads? My drivers is toast and all I've found on the web is pricey new ones. Facebook market place and Craigslist have been no help as it seems most have power windows. 

If you go to Crutchfield.com you can pick the truck and it will show you what fits and what adapters you'd need. LMC probably has the door pads but not sure on price. Facebook groups are good for partouts.

Also 6x9s fit in the rear with a little massaging.

Who else has a seat that is falling apart and what have you done about it?

white_fly said:

Who else has a seat that is falling apart and what have you done about it?

Mine was mostly normal wear and sun-fading/degradation.  I got stock type replacement upholstery from LMC Truck and did the re-cover myself.  Came out pretty good.  Heck, that was probably ten years ago.

white_fly said:

Who else has a seat that is falling apart and what have you done about it?

My drivers seat in my 96 was trashed. Found a FB marketplace part out and swapped it our for one that was much better.

1991 C1500 Silverado Mk III, 5.7 and 3.42 gears.  Sometime DD, trash hauler, tow-pig and home improvement store rig.  Odometer stopped at 279,000 miles soon after I got it in 2011. 

You guys are the worst. Have me looking at the "spare" GMT400 Tahoe in my FILs backyard, wondering what an LS Swap and 2/4 lowering kit would do for me..

No photos, but my father had an old '95, 4x4, 350 TBI, extended cab short bed. It was the blue-and-silver two-tone paint with a blue interior. My brother-in-law gave it to him for free (it had like 200k miles on it and he had just bought an '05) and my father proceeded to drive the hell out of it. We moved a lot of firewood with that old truck, yanked a porch off a house that was getting a remodel, I did some burnouts with it and hit a deer (neither of which he knows about) and general just used it as a truck. At 280k, one of the original ball joints broke, and the other 3 were still factory at ~300k when we retired the truck after the driveshaft corroded so bad that it snapped in half when my mother went to pull out of a parking lot. By that point, the frame had developed a couple cracks from rust, and the cab had settled so bad it hit the driveshaft whenever you had a load in the bed. But the unopened 4L60E still worked as it was supposed to and the all-original 350 still made 45psi of oil pressure going down the road. Just a terrific old rig.

classicJackets (FS) said:

You guys are the worst. Have me looking at the "spare" GMT400 Tahoe in my FILs backyard, wondering what an LS Swap and 2/4 lowering kit would do for me..

Or just drive it, and don't modify anything. They're really good for that.

Floating Doc (Forum Supporter) said:

classicJackets (FS) said:

You guys are the worst. Have me looking at the "spare" GMT400 Tahoe in my FILs backyard, wondering what an LS Swap and 2/4 lowering kit would do for me..

Or just drive it, and don't modify anything. They're really good for that.

I already have an Expedition to do the actual "needed" things with lol, it just looks pretty cool and I think an LS swap into an almost bolt-in platform would be great

classicJackets (FS) said:

Floating Doc (Forum Supporter) said:

classicJackets (FS) said:

You guys are the worst. Have me looking at the "spare" GMT400 Tahoe in my FILs backyard, wondering what an LS Swap and 2/4 lowering kit would do for me..

Or just drive it, and don't modify anything. They're really good for that.

I already have an Expedition to do the actual "needed" things with lol, it just looks pretty cool and I think an LS swap into an almost bolt-in platform would be great

 

Yeah, they are great when modified, too.

This is a major moment for me for no other reason than finally posting my first image here on the forum ......BoooYaaa!!!!! And yes there'll be more of this 

759NRNG (Forum Partidario) said:

 

This is a major moment for me for no other reason than finally posting my first image here on the forum ......BoooYaaa!!!!! And yes there'll be more of this 

I regret that I have but one thumb to give.

Floating Doc (Forum Supporter) said:

88 Silverado c20, 350/700r4. 3.73 fourteen bolt with an aftermarket limited slip.

Bought in eastern California, owner moved to west Texas. Willed to his grandson, then given to me about 12 years ago.

Milage is unknown, was about 243,000 when the odometer quit in about the year 2000. Estimated at 350,000 when I got it.

February 2018, bringing home my first Miata.

February 2020, thousand mile tow over four days.

For several weeks last winter, I had a baffling problem, where the truck would run like normal, but needed a fuel prime to start. 

Of all things, it turned out to be the distributor.

The thousand miles of towing the green miata started the day after it was replaced, so obviously I've got confidence in this truck.

Still, I was pretty worried when it started missing on the way home recently. I didn't look at it for a week, since I've been having some weird car problems lately, and it took months to diagnose last time.

Loose plug wire. 

On the other side of the fence, is my neighbor's GMT 400, also an 88. It hasn't been driven in the 9 years we have lived here, but I've heard it run, and it's been moved every couple of years. 350, turbo 400.

I don't think it's worth saving. 

rattfink81 said:

So hope it's cool if I ask a Gmt400 question in this thread. 
 

looking for speakers to fit in the factory dash and the factory spot on the b pillar. They look funky and I didn't have much luck on the webs for cheap replacements. 
 

also any one got a line on manual window interior door arm rest pads? My drivers is toast and all I've found on the web is pricey new ones. Facebook market place and Craigslist have been no help as it seems most have power windows. 

In reply to solfly :

Really? Guess I'll have to stop at a Chevy dealer and see. 
 

I finally ordered up and installed some 4x6 speakers and carefully removed the failing headliner. Cardboard is still good but the adhesive and clips that held it up had turned to dust.  Got a seat cover and center console coming from amazon.