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22 Eargesplitten posted:Does anyone know where to find the gear ratios of the various transmissions and years? I've got a '92 with a 5 speed manual and no tachometer. I've never driven a V8 before so I don't know what different RPM sound like. I'm going to be towing soon so I expect I'll want to be in 4th for that but I want to calculate RPMs to make sure that I don't sit near redline. I swear for a generation that talks about "hur hur kids today can't drive stick" everyone that owns one of these chose the automatic. Not a direct reply, but we had a mid-'90s K1500 with a V8 and 5 speed and no tach. It never really mattered, because the engine fell flat as soon as it got out of the torque range. In other words -- just use some mechanical empathy and it'll be fiiiiiine.
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Jul 22, 2022 17:41
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EVERYWHERE 
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Yeah, what meatpimp said. Fourth gear will not have you anywhere near redline at any reasonable speed. Also, with a manual there's no underlying reason not to grab fifth gear if conditions warrant. The whole reason automatics used to get told to tow outside of overdrive is that their shift mapping is based on an unloaded truck and letting it grab overdrive on its own will result in the transmission hunting back and forth, generating a lot of heat and wear very quickly. Modern automatics in a vehicle meant for towing will have an alternate shift map for heavy loads that eliminates hunting for gears, so it's less of an issue than it used to be.
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Jul 22, 2022 18:06
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Okay, I've been careful because it's an old engine and I wasn't sure what safety measures were in place to prevent floating a valve or something. I put the tire diameter, diff ratio, and 1:1 into a RPM calculator and apparently I'd be humming at 2500-ish at 55-60. I'll keep that in mind about fifth gear too but I doubt I'll want to take it too much faster even though I have trailer brakes.
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Jul 22, 2022 19:01
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22 Eargesplitten posted:Does anyone know where to find the gear ratios of the various transmissions and years? I've got a '92 with a 5 speed manual and no tachometer. I've never driven a V8 before so I don't know what different RPM sound like. I'm going to be towing soon so I expect I'll want to be in 4th for that but I want to calculate RPMs to make sure that I don't sit near redline. I swear for a generation that talks about "hur hur kids today can't drive stick" everyone that owns one of these chose the automatic. Your truck probably has the HM290. If that's the case, here's a nice paper with some good info on it: http://tcase.rsgear.com/articles/1993_03.pdf
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Jul 22, 2022 19:39
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I can’t imagine spending a day with the transmission and not being able to hear and feel where to shift, and what makes the truck happy. If it’s screaming at you you should have shifted earlier if it’s stumbling and sucking you need to be in a lower gear.
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Jul 22, 2022 19:47
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22 Eargesplitten posted:Okay, I've been careful because it's an old engine and I wasn't sure what safety measures were in place to prevent floating a valve or something. You've got a TBI GMT400, right? 50/50 on it having a rev limiter, but it also probably barely makes enough power to be able to get to valve float outside of neutral, first, or second gears. You can have that thing loving screaming and it just won't make enough power to rev higher.
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Jul 22, 2022 19:48
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My 92 c2500 has a nv3500 behind the tbi 5.7l, no tach but you know when it wants you to shift. It also has a shift light on the dash that I usually ignore. I've heard the nv4500 has a weak 5th gear and that's why you don't want to tow in 5th, not as sure about the lesser transmissions. You'd probably be fine if you're downshifting for bigger hills and only keep it in 5th on flat ground.
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Jul 22, 2022 21:18
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Boaz MacPhereson posted:Your truck probably has the HM290. If that's the case, here's a nice paper with some good info on it: http://tcase.rsgear.com/articles/1993_03.pdf I thought it was the 5LM60 but the FSM doesn't have a great amount of information on which transmission is on there. The shift light comes on at 40-45 in 4th gear but apparently that's like 1500RPM so  . The serpentine belt is louder than I'm used to even with a new one and the pulleys and tensioners replaced, not sure if it's the PS pump or alternator or what. Not seeing any PS pump leak after pressure washing the engine bay at least. So it sounds like it's screaming but then when I have the windows down the engine is rumbling at low RPM. I'm also not used to having so much torque only driving 4 cylinders and one six cylinder auto, it will pull smoothly from what's apparently roughly 800RPM.I think part of it might be my dad always had it running at pretty low RPM judging by the way it sounded when he drove it, which might explain how he managed to get high teens out of a 5000 pound truck with a 350. I learned to drive stick on it but I just listened to the shift light there because I knew nothing about cars. 22 Eargesplitten fucked around with this message at 22:45 on Jul 22, 2022 |
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Jul 22, 2022 22:39
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That shift light is probably optimized for no-load mpg optimization.
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Jul 22, 2022 23:00
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I think I figured it out. It's speed-based, not gear-based. I also get a "shift up" at 60-65mph, and given that there's no up from 5th I have to assume that's for 4th gear.
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Jul 23, 2022 01:15
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22 Eargesplitten posted:I think I figured it out. It's speed-based, not gear-based. I also get a "shift up" at 60-65mph, and given that there's no up from 5th I have to assume that's for 4th gear. I don't know for sure on these trucks, but most of the upshift lights were based on a very simple calculation of engine RPM vs. vacuum.
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Jul 23, 2022 01:23
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I need to hunt down a new e-brake pedal for my '13 GMT900. apparently it's NLA from the dealer.
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Jul 23, 2022 02:20
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22 Eargesplitten posted:I think I figured it out. It's speed-based, not gear-based. I also get a "shift up" at 60-65mph, and given that there's no up from 5th I have to assume that's for 4th gear. Ignore that light, it's dumber than you are. A good solution for it is to pull the gauge cluster and apply a square of electrical tape to the surface so it won't bother you again.
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Jul 23, 2022 18:38
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wallaka posted:Ignore that light, it's dumber than you are. A good solution for it is to pull the gauge cluster and apply a square of electrical tape to the surface so it won't bother you again. Isn't it just a bulb to be removed or is it an integral led or something?
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Jul 23, 2022 19:17
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22 Eargesplitten posted:Does anyone know where to find the gear ratios of the various transmissions and years? I've got a '92 with a 5 speed manual and no tachometer. I've never driven a V8 before so I don't know what different RPM sound like. I'm going to be towing soon so I expect I'll want to be in 4th for that but I want to calculate RPMs to make sure that I don't sit near redline. I swear for a generation that talks about "hur hur kids today can't drive stick" everyone that owns one of these chose the automatic. One of the factory service manual books might have it, I think that's where I found it for my 95. You can get pdfs of reasonable quality on GMT400 dot com. Strongly recommend grabbing them if you haven't already.
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Jul 23, 2022 23:27
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22 Eargesplitten posted:The shift light comes on at 40-45 in 4th gear but apparently that's like 1500RPM so Completely different car (but still GM), but my Saturn would often throw the upshift light as low as 1100 RPM. It also threw it a few times in reverse.  I learned very quickly the purpose of that light was to make me lug the everliving poo poo out of that engine. randomidiot fucked around with this message at 01:33 on Jul 24, 2022 |
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Jul 24, 2022 01:31
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StormDrain posted:Isn't it just a bulb to be removed or is it an integral led or something? On my TJ it was an LED. I desoldered it because it was that loving annoying. I'd expect it to be an incandescent on a GMT400.
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Jul 24, 2022 02:02
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STR posted:Completely different car (but still GM), but my Saturn would often throw the upshift light as low as 1100 RPM. It also threw it a few times in reverse. As the drivetrain is usually the most reliable part of a GM product, they need you to wear it out so you’ll buy a replacement.
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Jul 24, 2022 03:36
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Advent Horizon posted:As the drivetrain is usually the most reliable part of a GM product, they need you to wear it out so you’ll buy a replacement. Since it's not a 4L60E I'm inclined to agree. He's probably not facing a surprise "Oops! All neutrals!" moment.
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Jul 24, 2022 12:45
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Yeah, that's part of why I bought this truck. Cosmetically it's falling apart, mechanically within the past 5000 miles of me buying it, it had a rebuilt transmission, rebuilt transfer case, and new radiator. Then I replaced the brakes and the shocks and now it's an ugly pig that drives perfectly. I made my trip fine, although going up a steep mountain pass was butt-clenching with how long I had to have the engine sitting at fairly high revs just to maintain 30mph.
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Jul 24, 2022 17:11
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As someone who just did a mountain road trip with an even slower vehicle, my advice is simple: momentum is your friend. Build momentum every chance you get. Also gently caress the loving FedEx trucks that always pulled out in front of me at the bottom of big hills, forcing me to brake and killing my momentum.
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Jul 24, 2022 19:38
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22 Eargesplitten posted:Does anyone know where to find the gear ratios of the various transmissions and years? Check the RPO codes in your glove box. I replaced one airbag sensor a year and a half ago for 80 bucks. Today?  Edit: oh, you meant all the available ones, not the ones installed in your vehicle I guess. Never mind. nitrogen fucked around with this message at 20:56 on Jul 24, 2022 |
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Jul 24, 2022 20:13
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GMT400 grilles from GM have gone from about $350 to 550 in the past year. It's a shame LMT's look like crap. Once you see the corners they cut, it's like the fedex arrow (for me at least). Edit: The RPO breakdown is in one of the pdfs from the truck forums. That's what it was...my memory is not so great sometimes.
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Jul 24, 2022 23:01
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I want to get a new spare tire for my truck because it looks like it's about 80% rust at this point, do I need specifically a wheel designed for that or can any wheel of the proper stud pattern and hub size work? It looks like it's a full size. I could always strap one into the bed but I like having as much space in the bed as possible. It's a '92 K1500 in case the difference between GMT400/800/etc matters.
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Jul 27, 2022 21:19
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You should be able to throw any 6 bolt half ton GM rim on a 1500. If you're near southeast Wisconsin I can give you an aluminum rim with a tire that holds air on it, I was given two extra sets with my 2dr Yukon.
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Jul 27, 2022 21:51
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Well, the Escalade is braking fine, but the caliper replacement broke it. Not surprising, I've known the rear shocks were sketchy for a while, and when I had it up, i noticed the boot were pretty torn up at the point of flexing that is exposed when it's jacked up. So... Service Ride Control message for the first time. Awesome. What's 2022 conventional wisdom on the Z55 automatically adjustable suspension rear shock replacement? I have a Dorman compressor right now, and an extra Dorman compressor on the shelf, but I don't know if I should replace with passive shocks, or what... thoughts? Edit: looks like bypassing the error code is easy enough with resistors. But I may need to change springs if I don't replace air shocks with air shocks... what about just getting a set of standard air shocks, pumping up to the level I want, and using the resistors to tell the computer to gently caress itself? meatpimp fucked around with this message at 22:11 on Jul 27, 2022 |
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Jul 27, 2022 22:01
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SpeedFreek posted:You should be able to throw any 6 bolt half ton GM rim on a 1500. It's this. The only reason wheels/tires are spare-specific is because when :gm: is making GBS threads out millions of trucks, saving $3 by getting a spare-only tire meant to go no more than 50 miles adds up quick. The only six-lug GM wheels that won't work are either more than 50 years old (1970 and down, they won't clear brake calipers) or so new that they're for a metric pattern instead of 6x5.5".
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Jul 28, 2022 05:26
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Toyota: still using 6x5.5”. American domestic brands: “Hurr, durr, I made up my own bolt pattern because metric”
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Jul 28, 2022 16:37
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Advent Horizon posted:Toyota: still using 6x5.5”. Sir the Land Cruiser thread is thataway. Ford went metric in the 90s with the SD, GM now too. Times are a changin' like back in the 80s and the ol GM four-hunnert platform was half imperial half metric. Sometimes on the same sub-assembly.
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Jul 28, 2022 16:49
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cursedshitbox posted:ol GM four-hunnert platform was half imperial half metric. Sometimes on the same sub-assembly. Little was more rage inducing than working on those.
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Jul 28, 2022 16:51
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So far it has seemed like everything is metric, but maybe things have just been close enough that a metric size mostly fits. The most frustrating thing was pulling the seats to clean the carpet, 15mm bolts with next to no clearance above them, and half of my wrench/socket sets don't even include 15mm because nobody uses it. I also haven't touched the engine or transmission, which I assume is most likely to still be SAE since lol at GM having updated anything they didn't have to since 1954. I can probably pick up a spare wheel for like $15 at a junkyard at worst since there's dozens of trucks from that era in every junkyard. I guess I might need a new spare tire holding/lowering assembly too.
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Jul 28, 2022 17:56
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I'm wondering if those might've actually been 5/8 or 9/16. Everything on ye olde engine will be SAE, the transmission is probably a mix because gently caress you that's why.
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Jul 28, 2022 18:21
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I'm sure they were 15 because it was the first thing I had done on the truck other than replacing the oil filter adapter gasket, topping off fluids, filling tires, and changing the air filter and battery. I had my SAE set out because I assumed that since it was an American truck it would be all SAE sizes. I went through everything in that range before I decided to try metric and it fit perfectly. The nice thing about this transmission is that I know it got rebuilt about 3,000 miles ago, along with the transfer case, because my dad's ex blew up the transmission somehow, and he got it fixed after she became ex and he already had another daily driver. So I'm hoping to avoid dealing with it for quite a while. Same deal with the shiny new radiator, he replaced it before he decided that he didn't want to keep working on a truck that mainly sat in a field. E: Actually that reminds me, do manual transmissions even have hookups for a transmission cooler? The radiator has a built-in transmission cooler that you can hook up but it isn't hooked up to the transmission. As far as I know that's only an automatic transmission thing but given that I sometimes tow with this thing it probably wouldn't be bad to have additional transmission cooling since it's having additional strain placed on it. 22 Eargesplitten fucked around with this message at 19:02 on Jul 28, 2022 |
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Jul 28, 2022 18:58
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16mm and 5/8 interchange. 14mm is alllmost 9/16. 15mm is an outlier. in the 80s the big threes' pickups were all a hodge podge of metric and imperial. some worse than others. the 400 is imo the worst offender. TH400 is imperial. 700r4 is a hodge podge of metric/imperial depending on the year. 4l60s are metric. nv3500/4500 afaik will be a hodgepodge depending on year of manufacture. Some manuals will have a cooler and pump. no manual transmission in a 400 will.
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Jul 28, 2022 19:34
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cursedshitbox posted:Times are a changin' like back in the 80s and the ol GM four-hunnert platform was half imperial half metric. Sometimes on the same sub-assembly. Sure, but the lug pattern can stay 5.5” because it’s not like the actual fasteners are SAE. 22 Eargesplitten posted:The radiator has a built-in transmission cooler that you can hook up but it isn't hooked up to the transmission. As far as I know that's only an automatic transmission thing but given that I sometimes tow with this thing it probably wouldn't be bad to have additional transmission cooling since it's having additional strain placed on it. Most manuals do not. A lot of aftermarket radiators have the automatic connections since most people have autos and it’s easier to leave that disconnected than make a second radiator just for the diminishing manual market. The auto coolers in a radiator are great for power steering, if you ever feel like you need more cooling in that system.
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Jul 28, 2022 21:47
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Advent Horizon posted:The auto coolers in a radiator are great for power steering, if you ever feel like you need more cooling in that system. Counterpoint: auto coolers in a radiator are poo poo. I've dealt with strawberry milkshake a few too many times.
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Jul 28, 2022 23:00
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22 Eargesplitten posted:lol at GM having updated anything they didn't have to since 1954. thats an interesting cutoff year to have chosen, since the small block chevy V8 debuted in 1955.
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Jul 29, 2022 05:24
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I looked it up on Wikipedia and it said it started production in 1954, I guess started production in '54 for the '55 model year?
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Jul 29, 2022 06:02
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22 Eargesplitten posted:I looked it up on Wikipedia and it said it started production in 1954, I guess started production in '54 for the '55 model year? ah, yeah that's probably likely it is pretty impressive that the first gen sbc lasted from 1955 until... 2003? in the vans? 1999 most places. other than the oil filter showing up in iirc '57 and the rod journal size changing in the late 60s (67?) and then the roller stuff in the 80s (cars) and 90s (trucks), they were pretty similar and shared parts through the whole run. i love that you could plunk late model speed parts onto a first-year motor and it would probably work
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Jul 29, 2022 08:43
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At some point in there the mechanical fuel pump provisions were removed.
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Jul 29, 2022 13:53
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