Past Contemplation, Bought a Full Size Expo rig. GMT400 Tahoe - ideas welcome

98dango

Expedition Leader
I love the 400 platform I have 3 yes there old and need love. I had 3 800 trucks 2 trucks 1 Tahoe. We liked the but there gone now for good reason.

I would look for a 4 door cheap and run with it. You have the skill and knowledge to make what you want.
 

tommyp

New member
I love the 400 platform I have 3 yes there old and need love. I had 3 800 trucks 2 trucks 1 Tahoe. We liked the but there gone now for good reason.

I would look for a 4 door cheap and run with it. You have the skill and knowledge to make what you want.

:iagree: That's the plan. Got my wife kinda on board last night. She doesn't want to go up in size but rather get a car for better mpg but no need to start looking for a car right now we can wait a few years on that. Her element will be fine for her for the time being. She is ok with me getting another project and I think if she drove the tahoe for a bit she probably wouldn't find it much harder to deal with than the element. So probably will start shopping for one in a few months.
 

98dango

Expedition Leader
My wife loved her Tahoe I did not like it's gadgets and gizmos that did not like to work.

Also I think a sas on one makes the drive better than stock
 

Bojak

Adventurer
I put my wife in a 97 tahoe 4x4 from her 2 door acord. I remember the night I took her to see it. She said, "I can't drive that, its huge!" 1 week later and I couldn't keep up with her when trying to follow her across town. She learned to love the tahoe alot. Me personally I would stay in the gmt 400 class. Imop the last really good gm's. The last that even stands a chance of becoming a classic.
 

tommyp

New member
Well here goes nothing. Bought a 99 yukon with a split transfer case for $500 today. Body in pretty decent shape especially for up here. Some rot in the back under the gate but rockers and everything else was fine. Or some light surface spots.

So off to find a np241 to do a manual t case conversion. Can't wait to start tearing into this thing but it will have to wait for winter.
 

justcuz

Explorer
T-case should be cheap and easy, a weekend job.
Next issue is to look for a 14 bolt semi float rear axle out of a pickup. The light duty K2500 still has 6 lugs but has huge rear brakes, a 9.5 inch ring gear with no carrier breaks so any set of gears you want can be installed.
Stay moderate on the lift by going with 3/4 ton leaf pack on your main leaf
Get some Ford F-150 or Expedition torsion bar keys to reindex the front for a mild lift.
Get some good gas shocks and traction device for the rear axle and it will be a bullet proof cruiser/dirt road/moderate 4 wheeler.
I have been tons of places in the desert southwest with vehicles with less modifications than this.
285/75x16 (32") tires fit easily with these suspension modifications.
 

tommyp

New member
T-case should be cheap and easy, a weekend job.
Next issue is to look for a 14 bolt semi float rear axle out of a pickup. The light duty K2500 still has 6 lugs but has huge rear brakes, a 9.5 inch ring gear with no carrier breaks so any set of gears you want can be installed.
Stay moderate on the lift by going with 3/4 ton leaf pack on your main leaf
Get some Ford F-150 or Expedition torsion bar keys to reindex the front for a mild lift.
Get some good gas shocks and traction device for the rear axle and it will be a bullet proof cruiser/dirt road/moderate 4 wheeler.
I have been tons of places in the desert southwest with vehicles with less modifications than this.
285/75x16 (32") tires fit easily with these suspension modifications.

Good points,

Already have a Tcase donor lined up. Going to try to pull the broken case tonight. Have to research the rear Axle. I was going to do a SAS and someone had a nice dana 60 pair on CL but I waited too long and missed them. I didn't realize how much those old high pinion Dana 60s are going for and how rare they are. So I may just end up with an ifs lift in the front if I can't find a Dana 60 or maybe a Dana 44 would work. I want to keep it low and on 35s so Sas isn't really needed.

But right now just want to get her on the road and straighten out any running issues that I may have.

IMG_1957.JPG


Busted *** case

IMG_1966.JPG



Little rusty in the back must have a leaky seal going to por 15 it.

IMG_2001.JPG


Where it is now. Barely fits in my workshop luckily this will be the last work done in there before the garage gets torn down and replaced with a much bigger space.

IMG_2037.JPG
 

justcuz

Explorer
If you have a solid axle swap in your future, I would stick with a GM 14 bolt full floater and find a Ford high pinion 8 lug Dana 44. The Dana 44 should be plenty for the Tahoe. The nice thing about both those axles is electric lockers are available for them. If your future is 35 or 37 inch tires then start collecting your solid axle parts and don't waste money on an IFS lift kit. Most are expensive, are poorly engineered and cause undo stress on ball joints and suspension bushings. Several solid axle Tahoes are on this site and Pirate 4x4. If you absolutely must have a Dana 60 front don't be afraid to use a ball joint front end. Everyone thinks the king pin ones are gold plated but the aftermarket heavy duty Dana 60's being beefed are mostly all ball joint axles.

The modifications I suggested are for the IFS use of the vehicle. I installed the 9.5 semi float 14 bolt in the rear of my 1993 Suburban. It is a much better rear axle than the 10 bolt and the bonus is the much bigger brakes. Full size Blazers and Tahoes only had 10 inch brakes on the rear.
The suspension modifications I suggested will net you 1.5 to 2 inches of lift (depending on the condition of your current springs and T-bars). 285/75x16 tires will fit your stock rims and also keep it cheap. Look at my Suburban in the last page of the suburban pictures thread parked behind the FJ Toyota. Jeremy has a lift and 33 inch tires and his has no more ground clearance than my Suburban.

3.73 or 4.10 gears are the preferred setup for 265 or 285 series tires.

In looking at your pictures again your rear springs look pretty healthy. I would just find some Ford keys to reindex your torsion bars to even the front with the rear. If you buy a 9.5 14 bolt semi float get the u bolts and saddle brackets too, the axle tubes are larger on the 14 bolt. I drill a 3/8 hole in the middle of the saddle bracket to let the mud and junk drain out and keep it from rusting.

The t-case looks like the front end was engaged and busted that side off. Make sure you check your front driveline. It almost looks like it was shock loaded and the front end came down on a hard surface and transferred the load back to the t-case.
 
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rayra

Expedition Leader
$500! Nice. That's a great place to start. Room for a lot of 'fixing' before it gets tough to justify. From your pics it doesn't look like it will take much to have a good solid truck. What do you have in mind to arrest the rust and prevent more? Use something like POR-15?

The missus drove a Celica and similar vehicles for years, before getting into a new '99 Tahoe. Been hooked ever since, can't stand riding in low vehicles where she can't see ahead in traffic. Drove it hard, commuting across L.A., got a good trade-in value moved into a '05 Z71. And now I've picked up that '02 Z71 Sub. The '99 had the 5.7 IIRC, and the current two have the 5.3L with a combined mileage of nearly 270k mi and not a single problem with 'weeping' water pumps. Don't know where that lore comes from.

More likely any coolant smell problem would come from the plastic couplings on the heater hoses, high on the firewall, where that plastic basks in the high heat. That reminds me I want to lay in a set of that hardware against future need. Especially now we have two such vehicles with near identical guts.

I did do a water pump replacement on hers at ~135k on what turned out to be a specious upsell by her dealer service dept. We were chasing a whirring noise that turned out to be her alternator shaft bearing (which I tore down and re-lubed, still fine). Dealer wanted $850 for alternator replacement. Similar price for water pump. I did the water pump for under $250, incl coolant, thermostat and upper and lower hose replacement and S-belt. She had taken her vehicle to the dealer during her warranty periods and wasn't much of a fan of my keeping a really old pickup as my daily driver. Somehow its mechanical foibles got turned into a negative view on my mechnical ability instead of the opposite. But once she got the sticker shock of those two suggested repairs and I showed her how much more inexpensively I could do the work, she got enthusiastic about my doing the work. Anyway, no cooling system problems before or since. I'm aiming to do the same preventative work on my Sub in the near future. Most of my mileage is in the desert southwest, freshening up the cooling system / making it a known baseline before taking it out there is important. Considering a preventative fuel pump replacement too. My Sub was a family / mom taxi in its previous life. That's where fuel pump problems seem to originate with these vehicles. Mom scuds about town on a 1/4 tank or less all the time and cooks the pump. And beats the **** out of the brakes and alignment. I found problems with both the latter when I first looked at mine,

brakes2_zps5135b06f.jpg
brakes1_zpsee747fdb.jpg



And I got to say I don't know how you folks in the rust belt can put up with it. My '02 spent it's life in Orange County CA and last month when I dug into the rear cargo area and wheel tubs etc it was basically as good as the day it came off the assembly line.

mess05_zpsgfoz2did.jpg
mess04_zpsn4hjvnzz.jpg
 
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tommyp

New member
If you have a solid axle swap in your future, I would stick with a GM 14 bolt full floater and find a Ford high pinion 8 lug Dana 44. The Dana 44 should be plenty for the Tahoe. The nice thing about both those axles is electric lockers are available for them. If your future is 35 or 37 inch tires then start collecting your solid axle parts and don't waste money on an IFS lift kit. Most are expensive, are poorly engineered and cause undo stress on ball joints and suspension bushings. Several solid axle Tahoes are on this site and Pirate 4x4. If you absolutely must have a Dana 60 front don't be afraid to use a ball joint front end. Everyone thinks the king pin ones are gold plated but the aftermarket heavy duty Dana 60's being beefed are mostly all ball joint axles.

The modifications I suggested are for the IFS use of the vehicle. I installed the 9.5 semi float 14 bolt in the rear of my 1993 Suburban. It is a much better rear axle than the 10 bolt and the bonus is the much bigger brakes. Full size Blazers and Tahoes only had 10 inch brakes on the rear.
The suspension modifications I suggested will net you 1.5 to 2 inches of lift (depending on the condition of your current springs and T-bars). 285/75x16 tires will fit your stock rims and also keep it cheap. Look at my Suburban in the last page of the suburban pictures thread parked behind the FJ Toyota. Jeremy has a lift and 33 inch tires and his has no more ground clearance than my Suburban.

3.73 or 4.10 gears are the preferred setup for 265 or 285 series tires.

Sounds like a plan. The 14 bolt full float would be 8 lug and match the 44 or 60. So I would swap them both over at the same time. Thanks for the help. I will keep an eye out for axles on craigslist. I am not sure if I will mess with the IFS crank prob just leave it and wait till I switch to address the suspension etc.
 

justcuz

Explorer
Look in your glovebox at the options list. If it says G80 you have a factory limited slip/locker. If you google G80 you can see a little YouTube video on how it works. They are decent but don't like shock loading, so be careful on heavy throttle application on loose surfaces.
Axles ratios are in there too, GT4 is 3.73.
Maybe the rust is from wet hunting gear stowed in there.
 

tommyp

New member
Look in your glovebox at the options list. If it says G80 you have a factory limited slip/locker. If you google G80 you can see a little YouTube video on how it works. They are decent but don't like shock loading, so be careful on heavy throttle application on loose surfaces.
Axles ratios are in there too, GT4 is 3.73.
Maybe the rust is from wet hunting gear stowed in there.

Will check it out when I get home. Any years that are preferable for the 14bff? Are they all the same width? I can redo perches if need be just seems like they came in a ton of different vehicles over the years. I would rather get one with disks and functional parking brakes then have to do a conversion on drums.
 

justcuz

Explorer
The years of that GMT 400 I don't think came with rear discs on the 14 bolt FF but the next generation did.
1999 trucks and 2000 and up 3/4 ton big block Suburbans spring perch width is wider I believe.
Also GMT 400 4wd rear axles are 3 inches wider than a 2wd drive one as I recall.
So your looking for a 2000 or newer 14 bolt FF for disc brakes.
 

tommyp

New member
Cool, Yeah I have found a few 2000+ 2500's with the 14bff 4.10 and g80. I think that is the way I will go. Pulled off the tailgate last night. Anyone know where I can source the hinge pins? the one I knocked out was pretty bent.

I ordered a new bumper from rock auto. I think I am just going to cut this one up to get it off. Was going to torch it but had some issues with my neighbors OA cutting torch not working correctly. The chrome is departing the old one pretty badly

IMG_2046.JPG


Going to try to temporarily fix the tailgate now and then this winter worry about really digging into the rust in the back end. Its not too terrible but I might need to get the body up off the frame a bit to get it all. It just seems like it is around the back here where the body mounts are. Probably salt off the rear tires getting thrown into the area. Doesn't seem like there is any undercoating back there.

This is the worst spot. This is the right tailgate hinge area. The hinge part that attaches to the truck is no longer attached. I am just going to cut this out once I get the bumper off and weld new metal in here. It is rotted underneath as well but I will just do the face for now and worry about that when I can pull the body off the frame a bit.

IMG_2045.JPG




The other side is starting to go as well. I didn't think it was that bad on this side on first inspection but when I started poking around it was soft in spots and underneath but not nearly as bad as the right/passenger side.

IMG_2047.JPG



For the bed I am going to use some SEM rust-shield. I have used chassis saver in the past and liked it. I want to see how this stuff is. It is cheaper and I can get it down the street.
 

tommyp

New member
Did a little work on it tonight. Cut off the old bumper, new one should be here tomorrow.

Did a little temporary cancer removal tonight and reattached the tailgate hinge. It was rotted pretty bad. I cut it back pretty far. Need to track down some hinge pins will check the dealer tomorrow. I am a little out of practice on my mig.

IMG_2073.JPG


Checked the rpo codes. It is a 3.73 with a G80. Debating if I want to do a 3.73 14bolt or just get a 4.10 and wait till I do the front sas. Not sure if 4.10s will be low enough for 35s. I want a good highway gearing in this car for decent mileage but low enough for trail use. I imagine I will get a 3.73 and install it with the stock front gearing and then change R&P when I do the sas.
 

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