02FailBlazer
Member
Thought it might be a good idea to compile some handy and hard to find information in one thread as it pertains to keeping GMT360 platform vehicles going. I'll start with a few things I've learned.
Vacuum brake boosters and the vacuum booster firewall gasket - OEM vacuum boosters are no longer available and even good aftermarket ones are a bit scarce, but I've recently learned that same-era GMT800 boosters might work for this platform. A cursory inspection suggests they can work but I don't have one on hand to compare with. But if they do work, this might expand the options available as parts become more scarce. Also, the vacuum booster gasket that I couldn't find for my TB is still available as GM part # 15974046, found by looking for vacuum booster gaskets for a 2002 Silverado 1500. As far as I can tell, this should be a perfect fit sans possibly needing to expand the center hole around the top a bit.
Given the above, there may be other GMT800 platform parts that are compatible with the 360 platform. If you know of any, please post the information here.
Regarding the gasket, it should be noted that it is very simple and one can be fabricated from a thin (1/16" or thinner, ideally) peice of low resilience foam rubber or other appropriate gasket material. Barring that, you could probably just clean up the firewall mounting surface and smear RTV on it.
Fuel filler hoses - OEM fuel filler hoses are long gone and the only aftermarket replacement left, the Spectra FNH140, may not be long for this world given the low stock levels I'm noticing. However, there IS a solution, even with GM screwing us by using two different hose ID's at each end. You'll need a (assuming I've got the dimensions right) 1-1/4" to 1" stepped reducer and two lengths of fuel hose - one with 1-1/4" ID, the other with 1" ID. All of these parts are available from fillernecksupply.com. This is the reducer you will need. I've checked for lengthwise clearance between the end of the fuel filler neck and the inlet on the fuel tank and there should be plenty of room. With that reducer, you will never need to worry about getting a specially made filler hose again, just fab your own. Do note that you will need 4 clamps instead of two, as you'll need to ensure the hoses stay secured to the reducer.
Shock dampener rings for the steering rack/inner tie rods - The shock dampener rings, GM part # 26088111, are plastic "cups" which fit over the inner tie rods. Presumably their purpose was to prevent marring/interference between the inner tie rod body and the inside of the rack housing in the event the rack twisted or moved. However, they can become detached and subsequently destroyed by normal movement of the steering rack. Replacements are unavailable unless you happen to find them intact inside of a parts car in a junkyard. I have a possible solution however - Use oil resistant heat shrink tubing to fabricate new dampener rings.
You will want something fairly sturdy with a high shrink ratio so it stays firmly attached to the inner tie rod. Use tubing with the closest fit to the tie rod body possible so that it will be on there TIGHT when it shrinks. I recommend shopping around on McMaster-Carr for something suitable. You should also check for clearance between the tie rod + tubing and the inside of the rack housing - even with the tubing on it should still clear the inside of the rack housing WITHOUT TOUCHING IT. To fabricate, simply cut the tubing so that it extends slighty past both ends of the inner tie rod body, thus creating "lips" when the tubing shrinks down which should bend around the tie rod body and prevent the tubing from slipping off. If you're feeling brave, you can also try tubing that has adhesive built in to it for extra security, but no promises that it doesn't leech into the rack lubricant and do weird stuff.
Starter motor positive battery cable terminal - This terminal connects the purple positive battery cable to your starter motor (yes it techincally attaches to the starter solenoid and not the starter itself, sue me). It runs out of the large wire loom that runs parallel to the engine. It should be the smallest of the three cables attached to the starter. The problem - this terminal is comically thin. Mine snapped in half, presumably while doing work on my intake. If you're doing any work around the starter, I highly recommend replacing this terminal with a thicker one as I did. Before doing this, ensure the new terminal fits and does not interfere or connect in any way with the adjacent terminals. Simply unbolt the positive battery cable from the starter, cut off the old terminal from the cable, strip the cable back to the appropriate length for your new terminal, and crimp on the new and improved terminal. Bolt positive cable back on to starter and enjoy the extra peace of mind.
OEM CV axles with torn boots - REBOOT, REBOOT, REBOOT. Common advice on the internet at large is to simply replace CV axles when boots tear as the effort isn't worth it plus the possibility of contamination having already damaged your axle. That's all well and good I suppose, but here's the kicker for us - THERE ARE NO MORE NEW OEM AXLES. The only axles left are cheap new aftermarket (and cheap aftermarket axles are famously of dubious quality) and the precious few Cardone remans still floating around while they're being liquidated. Your only other option to acquire an OEM axle is to pull one from a parts car. So, if your OEM axle isn't clicking/vibrating/etc. and just has a torn boot, REBOOT IT.
I swapped my driver's side axle due to having had a torn boot for a long time and I'm still kicking myself for tossing the OEM axle, but I hadn't learned what I know now. But that said, if for some reason you absolutely need to get a new axle instead of refurbing an OEM axle, I will tentatively vouch for the Trakmotiv GM8135. I haven't driven many miles on it, but the fit was perfect and at least up till now it has not vibrated or otherwise changed the characteristics of my TB. More accounts of the use of new aftermarket axles are welcome, maybe we can determine if one brand is actually better than another.
Shift linkage bushing - There is a plastic bushing which attaches your shift cable to the shift lever/arm on the transmission. This bushing can disintegrate, leaving you without the ability shift the transmission from within the cab. Dorman makes a replacement, part # 14057, but it's not great and doesn't fix the problem created by the OEM design. There is what looks like a slightly better model avaialble from bushingfix.com, though I have not used this one myself. There is however a more permanent fix - this metal shifter cable repair pin from ATF. This should never fail, unlike the plastic OEM bushing. If you want to or need to use one of the plastic bushings, I STRONGLY recommend buying two and keeping the spare inside the vehicle so you don't get stuck without the ability to shift safely. Hell, carry one anyway. They're cheap, small, easy to install, and can save you from a massive headache out on the road.
More will be added as more is learned...
Vacuum brake boosters and the vacuum booster firewall gasket - OEM vacuum boosters are no longer available and even good aftermarket ones are a bit scarce, but I've recently learned that same-era GMT800 boosters might work for this platform. A cursory inspection suggests they can work but I don't have one on hand to compare with. But if they do work, this might expand the options available as parts become more scarce. Also, the vacuum booster gasket that I couldn't find for my TB is still available as GM part # 15974046, found by looking for vacuum booster gaskets for a 2002 Silverado 1500. As far as I can tell, this should be a perfect fit sans possibly needing to expand the center hole around the top a bit.
Given the above, there may be other GMT800 platform parts that are compatible with the 360 platform. If you know of any, please post the information here.
Regarding the gasket, it should be noted that it is very simple and one can be fabricated from a thin (1/16" or thinner, ideally) peice of low resilience foam rubber or other appropriate gasket material. Barring that, you could probably just clean up the firewall mounting surface and smear RTV on it.
Fuel filler hoses - OEM fuel filler hoses are long gone and the only aftermarket replacement left, the Spectra FNH140, may not be long for this world given the low stock levels I'm noticing. However, there IS a solution, even with GM screwing us by using two different hose ID's at each end. You'll need a (assuming I've got the dimensions right) 1-1/4" to 1" stepped reducer and two lengths of fuel hose - one with 1-1/4" ID, the other with 1" ID. All of these parts are available from fillernecksupply.com. This is the reducer you will need. I've checked for lengthwise clearance between the end of the fuel filler neck and the inlet on the fuel tank and there should be plenty of room. With that reducer, you will never need to worry about getting a specially made filler hose again, just fab your own. Do note that you will need 4 clamps instead of two, as you'll need to ensure the hoses stay secured to the reducer.
Shock dampener rings for the steering rack/inner tie rods - The shock dampener rings, GM part # 26088111, are plastic "cups" which fit over the inner tie rods. Presumably their purpose was to prevent marring/interference between the inner tie rod body and the inside of the rack housing in the event the rack twisted or moved. However, they can become detached and subsequently destroyed by normal movement of the steering rack. Replacements are unavailable unless you happen to find them intact inside of a parts car in a junkyard. I have a possible solution however - Use oil resistant heat shrink tubing to fabricate new dampener rings.
You will want something fairly sturdy with a high shrink ratio so it stays firmly attached to the inner tie rod. Use tubing with the closest fit to the tie rod body possible so that it will be on there TIGHT when it shrinks. I recommend shopping around on McMaster-Carr for something suitable. You should also check for clearance between the tie rod + tubing and the inside of the rack housing - even with the tubing on it should still clear the inside of the rack housing WITHOUT TOUCHING IT. To fabricate, simply cut the tubing so that it extends slighty past both ends of the inner tie rod body, thus creating "lips" when the tubing shrinks down which should bend around the tie rod body and prevent the tubing from slipping off. If you're feeling brave, you can also try tubing that has adhesive built in to it for extra security, but no promises that it doesn't leech into the rack lubricant and do weird stuff.
Starter motor positive battery cable terminal - This terminal connects the purple positive battery cable to your starter motor (yes it techincally attaches to the starter solenoid and not the starter itself, sue me). It runs out of the large wire loom that runs parallel to the engine. It should be the smallest of the three cables attached to the starter. The problem - this terminal is comically thin. Mine snapped in half, presumably while doing work on my intake. If you're doing any work around the starter, I highly recommend replacing this terminal with a thicker one as I did. Before doing this, ensure the new terminal fits and does not interfere or connect in any way with the adjacent terminals. Simply unbolt the positive battery cable from the starter, cut off the old terminal from the cable, strip the cable back to the appropriate length for your new terminal, and crimp on the new and improved terminal. Bolt positive cable back on to starter and enjoy the extra peace of mind.
OEM CV axles with torn boots - REBOOT, REBOOT, REBOOT. Common advice on the internet at large is to simply replace CV axles when boots tear as the effort isn't worth it plus the possibility of contamination having already damaged your axle. That's all well and good I suppose, but here's the kicker for us - THERE ARE NO MORE NEW OEM AXLES. The only axles left are cheap new aftermarket (and cheap aftermarket axles are famously of dubious quality) and the precious few Cardone remans still floating around while they're being liquidated. Your only other option to acquire an OEM axle is to pull one from a parts car. So, if your OEM axle isn't clicking/vibrating/etc. and just has a torn boot, REBOOT IT.
I swapped my driver's side axle due to having had a torn boot for a long time and I'm still kicking myself for tossing the OEM axle, but I hadn't learned what I know now. But that said, if for some reason you absolutely need to get a new axle instead of refurbing an OEM axle, I will tentatively vouch for the Trakmotiv GM8135. I haven't driven many miles on it, but the fit was perfect and at least up till now it has not vibrated or otherwise changed the characteristics of my TB. More accounts of the use of new aftermarket axles are welcome, maybe we can determine if one brand is actually better than another.
Shift linkage bushing - There is a plastic bushing which attaches your shift cable to the shift lever/arm on the transmission. This bushing can disintegrate, leaving you without the ability shift the transmission from within the cab. Dorman makes a replacement, part # 14057, but it's not great and doesn't fix the problem created by the OEM design. There is what looks like a slightly better model avaialble from bushingfix.com, though I have not used this one myself. There is however a more permanent fix - this metal shifter cable repair pin from ATF. This should never fail, unlike the plastic OEM bushing. If you want to or need to use one of the plastic bushings, I STRONGLY recommend buying two and keeping the spare inside the vehicle so you don't get stuck without the ability to shift safely. Hell, carry one anyway. They're cheap, small, easy to install, and can save you from a massive headache out on the road.
More will be added as more is learned...
