Anybody know what the final drive ratio in a 6.5l blazer is? Or better yet where I could source a new rear end?
Printable View
Anybody know what the final drive ratio in a 6.5l blazer is? Or better yet where I could source a new rear end?
Look at the RPO tag in the glove box, probably 3.73's and I think is GT5?
6.5L Blazer so one of the super rare GMT400s? It's probably 3.42s.
Gear Ratios:
Code Ratio
GU2 2.73
GU4 3.08
GU5 3.23
GU6 3.42
GT4 3.73
GT5/GT8 4.10
Its a GT4, 3.73. I believe the only other option in this chassis was the GU6.
I don't have any of the tools or expertise to rebuild the diff, so ideally I'd just like to swap in a complete assembly. I definitely have the tools and skills to pull and axle and put in a new one, we just did a tcase swap on my buddy's trailblazer today.
I'm not entirely sure what the problem is, I just know I'm getting what basically amounts to a jackhammer sound from the back end, it was going away when power was not applied, but in a trip across town appears to have gotten worse, and is now constant when rolling.
I can rebuild it for you.
Cost and timeframe? I don't really have a way to transport the truck or the axle.. I could offer a garage and space in the basement if you wanted to do it here. Hell, I could have it pulled and reinstall it. I just don't know the first thing about opening up a diff and getting clearances right when it goes back together.
I will probably pull the rear cover tomorrow to at least get a look at it and see what is going on.
fritz does some excellent work.
If absolutely needed I got a pick up with an empty bed if it came to that.
Sounds like a universal joint to me.
But anyway, I'd just buy a whole set of gears on an open or G80 differential, complete with shims, and put it in your case. A little slop never hurt a 200hp powertrain. Just need a new crush collar, 4 quarts of 75w140, and a lot of brake cleaner.
there is no slop in the rear driveshaft, and the sound cycle when slowing down is too slow to be the drive shaft, it sounded like it was about every wheel revolution, which is what pointed toward the diff.
I can get the axle.
PMed.
Pulled the rear shaft (thinking maybe I can FWD it for a few days), and it still clunked in reverse... tried to drop it in drive, and the rear end locked up solid. Backed up some more, and I got a half turn before it locked up again... rinse repeat, got it backed into the driveway again. Rear end is definitely fubared unless someone knows of a reason a rear end locks itself in forward gears with no input hooked up. Left wheel was definitely locked solid, I'm assuming the right was as well, it looked like the driver's side was trying to turn backward, as the truck was on a crowned road, more weight on the right side. I believe this truck has an open diff, last time I jacked it up without chocks, it rolled back, pass side tire turning forward.
After some research, it appears that for the added cost of a $25 conversion u-joint, I can swap in a 14 bolt semi-floater instead of a 10 bolt. I see no reason not to pursue this option instead of rebuilding the 10 bolt. And from what I've found, 14 bolts are actually cheaper? Less demand because they break less maybe? doesn't make much sense to me.
If I can get a 14 bolt with a locker for a decent price, between that and the 1.5" lift block I'll probably throw in (seeing as I seriously doubt these u-bolts will come off cleanly I may as well!) I may actually be GLAD this happened. haha.
get a real 14 bolt (full float) and do a SAS for the front down the road. a 2500 suburban of the same period should bolt right in
What did they put a six lug 14 bolt in?
Some of the OBS 3/4 trucks and vans (what rhyme or reason vs the 8 bolt semi? no idea.. looks like most or all gear ratios were available with either hub). Vans are the same width as 4x4 trucks, but spring perches are different width, 4x2 trucks the axle itself is 3" skinnier (as long as you're swapping from 4x4 or 4x2 to the same, the width is the same between 10 and 14 bolt). From the research I did, the only differences (provided you have the 11" drums on your 10 bolt, 10" is an option as well on the 10 bolt) is the u-joint size.. and local auto parts stores stock the conversion joint from 1330 to 1350...
However, the guy I was going to buy the 14 bolt from wants to keep it with the front diff (for $400, not a bad price), but hes also got a 10 bolt locker in the ratio I need for $150. So... $150 to have my truck back running it will be. Upgrades maybe some day?
My truck is essentially a 3/4 ton 2 door suburban (even has the bumper cutouts), with 1/2 ton axles and springs.
So... yes.
Isn't springs and axles what the difference between half and three quarter ton trucks? this is all so very confusing.
No, its a half ton, It just got the 4L80e because it has the 6.5l. I assume it also go the bumper with the cutouts (shared with the bigger OBS trucks) because the cooling system is weak, to say the least.
My point was only that the interchange for the rear ends with the 3/4 tons (6 bolt) is as simple as a conversion joint because everything was built with common dimensions.
Alternatively, the 10 bolt yoke will bolt to the 14 bolt, but... why?
Is your truck and old Army Blazer?
This is still the 89-99 style... not sure what you're referring to.. the bumper difference is that mine has the holes in the bumper like the higher rated trucks. The 1500's without the 6.5 do not. See pic below:
http://media.ed.edmunds-media.com/pi...85-300x189.jpg
No. Civilian truck, just with the 6.5 in it. Standard production, they just didn't make too many of them with the 6.5 (plus when they went to IFS they basically didn't appeal to the K5's target market anymore)
I thought the bumper holes were specific to the 6.5, even on half tons. I remember as a kid when I would see the bumper holes I'd say, "there's a 6.5TD". I know big block 25-35 k trucks trucks had a conventional bumper with no airdam.
I guess one could say these half ton diesels were the early "1500HD" models like was offered in the GMT 800's.
That could be, and would actually make more sense (with the cooling issues they have). I never really paid attention to OBS 3/4 or 1 tons intricacies until this truck started prompting me to borrow parts from them. lol
Like he said, calling it a 1500HD is probably the most accurate description, but no, it is (at least officially) just a 1500 blazer with a diesel in it. I was speaking to a functional level, not the label/badge. To my knowledge there has never been a 3/4 ton 2 door SUV (blazer/yukon/tahoe) on the GMT400 platform. The fact that it was never a factory option on the platform but still bolts in was part of why I wanted to do it.
Here is the best thread I found for anyone working on an OBS/NBS and considering doing some basic upgrades.
You have a 1/2 ton vehicle with a 6.5TD and a 4L80e in it. There is nothing 3/4 ton about it other than it has torsion bars and keys to hold up the engine. It's not even a high GVW vehicle like the 14SF GMT400 half ton pickups (7600lbs GVW maybe? I forget.) It's a far cry from the GMT800 1500HDs with their beefier suspension and 8 lug 14SF. The 1500HDs were basically a wimpy front end 2500LD with a shorty box.
The 14SF is larger than the 10 bolt. I believe it's around 2" longer from tube centerline to trunnion centerline. So, unless you're going to lift it, it will likely need the driveshaft shortened. The distance from the tube centerline to the top of the spring plate will change (resulting in a lifted vehicle). You have to get new spring plates and U-bolts also. Keep the S44 joint and don't run a bastard joint. Most of the time GM used S44 on a 14SF unless it was a manual transmission (then they usually used a 1350). Don't forget to pay attention to spring perch location and shock mount location.
It's easy to swap, but not as easy as you think it is. I have at least one of every GM truck axle sitting around except for a disc brake 7.625, a large pinion 10 bolt (showed up with the 2007+ AWDs), and a 11.5". I may not have an 80s G/P series 14SF van axle anymore but who cares about 5 on 5 crap anyway?
The 8.5" 30 spline 10 bolt is a fine axle. It usually only breaks when it has a grenade-lock in it or when people do one wheel peels on gravel then hit concrete or asphalt. The GMT800 style fixed a lot of shortcomings including larger side gears and a beefed carrier. The 2007+ ones that showed up with the AWD Denalis and Escalades got a larger pinion bearing.
If your still thinking about doing this I have the stock 14 bolt out of my plow truck, a 99 chevy pickup, same body style as your blazer. It has an open diff and 4.10 gears, huge drum brakes, 8 lug... Make me a fair offer and its yours.
wrong gears, wrong lug... thanks, but I'm married to my wheels and tires for the moment. I could go to 4.10 (stepping up to a 285/75/16 tire so it'd almost be a wash), but I don't want to be without 4wd, and I REALLY don't want to screw with doing the front right now.
I'll get ahold of you if this truck ends up staying with me longer than I think and I start considering a SAS. I believe there is a ford dana 44 that makes a nice front axle for this thing. (no research done other than watching the powerblock episode on it lol)
I took a floater today.
Win.
Here are the tires I was picking up when the rear end popped. Got the fronts mounted in optimistic hopes that tomorrow around now, she'll be back in operational form. Notes to self: 1) 4x4 unlocks when the vehicle is shut off, didn't know that til now. Luckily it appears this type doesn't require the wheels to tur in order to engage 2) It didn't leak out of the back of the tcase until I moved it (had to back it up to move the wheel chock)... which I find odd because it is parked with the nose pointed down hill, and I don't think it leaked at all last time I moved it. 3) my duct tape cap on the back of the t-case didn't do SHIT. lol
http://i921.photobucket.com/albums/a...9/34829be3.jpg
Nice. What size? My truck needs tires, bad. Needs a lot actually; but tires are second on the list. Gonna look for some used rugs until I can sock away loot for wheels and 305's. It needs springs, so I may just lift it and go with 35's. But I don't wanna lose too much towing/hauling ability lifting it, so I may not. I'm unsure of many things at this point.
lolz. I wanted to do 305/70's but I found this set of M/T's for $200. With the side biters, they look a lot bigger than 285 IMO, especially compared to the rear tire pictured which is a 265/75/18. And technically its more like $350 if you count the axle I blew in the process of getting em. And I paid 140 for the wheels, and spent probably 3 hours refurbishing them.
So, the guy I was going to but a 10 bolt from for $150 got plastered last night, and didn't feel like pulling the axle, so he sold me the 14 bolt he had (reported 75K on it) for $200. I'm super happy to report, the 14 bolt is in and running. I installed it with a 2" lift block and at near full droop, it looked like the pinion angle and slip yoke looked good. Did well on a test drive around the block. Truck has a bit of rake now, but I'll jack the torsion bars a bit to balance out some of that.
Had some minor complications which were fixable (broken brake line, frozen rotor, missing 1 u-bolt strap), only open issues are: the driver's side bleader broke off, so its unbled on that wheel and brakes are spongy, and I did not hook up the e-brakes.
That axle is one heavy bitch (I've read anywhere between 330 and 550. I can handle the 10 bolt on my own (those of you who've met me know I'm in the "lanky fucker" category). Getting the 14 bolt under it and bolted up with nothing but a pair of floor jacks (buddy with a trans jack showed up about 2 hours after it was bolted in) on my own was... a challenge.
New tires make for an interesting vibratory sensation at low speeds... so thats cool. lol