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What gears would this truck have?

Fry

1/2 ton status
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Sask, Canada
86 Blazer, diesel, 700R4?
I'm going to look at some diffs that came out of it and am hoping they would be 3.73 so I can junk my 3.08 what do you guys think? BTW I can't afford 1 tons right now and my dana 44 decided to take a poo over its axle. /forums/images/graemlins/smirk.gif
 
I think that the military blazers had that drivetrain combo and generally came with 3.08s. It would make sense that they would have tall gears because of the diesel. You need to find a truck that had a 6 cyl in it, those usually have deeper gears.
 
military blazers didn't come with 700Rs did they?
I was thinking that with a 700r that they might possibly be lower.
Anyone else wanna guess?
 
Military CUCV Blazers came stock with TH400 trannies and 3.08 gears. As for what gears are in the truck you are looking at, hmmmm... /forums/images/graemlins/thinking.gif I'd hate to just guess, but it may be 3.73s since it has the OD 700R4. I bought a whole front 10-bolt from a junk yard once and it had 3.73s and a 700R4 so I'd say your chances are about 50/50 /forums/images/graemlins/thumb.gif
 
I was thinking a 700R4 might rev too low on the highway since the 400 seems to be a fairly low geared transmission so you'd think they compensate with lower gears.
Anyway keep your fingers crossed as I would really like to pick these up they are around $200 and the front as all been rebuilt including steering & braking parts along with new warn hubs, etc, etc.
If anyone has any more insight I'm all /forums/images/graemlins/ears.gif
 
you guys are like the all knowing Gods of K5s someone must know, I need to know if they are worth my time...someone?
6.2+700R4=GEARS? /forums/images/graemlins/thinking.gif
 
you really think they'd be that high? i would think that it would make the RPMs to low on the highway in overdrive, considering that a TH400s 3rd gear is way lower than 700r4s overdrive and the diesel used a 400 on the CUCVs with 3.08 as previously discussed.
Sorry I'm trying to add reasoning to this in an effort to make it true, but GM didn't always have the best reasoning behind everything they did. Anybody out there have a diesel & a 700r4?
 
I highly doubt that there is one correct answer. Gm had a real habit of putting tall gears in all of the trucks in the 80s, even those with OD trannies. They were just trying to get every little bit of fuel mileage possible out of them. My money still says 3.08s.
 
My truck came from the factory with a 305 and 700R4 and 2.73 gears. Why wouldn't a torquier Diesel truck come that way?
 
I guess I can wait and see, really hate to waste a 2hr trip for nothing, but the guy selling them says he has a chev on 44s in his driveway so that'd be worth seeing I guess. He also said that he had a 426 sbc or something destroked that hes selling dynoed at 680hp, I'm not to sure how you'd get 426cubes out of a SBC but I'm not up on that stuff.
I find it odd that hes selling diffs yet he never even looked to see what the ratio was. It might even be stamped on the cover right? I just don't want to be spilling gear oil all over his lawn counting teeth or looking for a ratio number.
I not sure what I should do if they are 3.08s though, my motor is so gutless right now that they are such a dog but its nice to have for the highway on the way to work, though 3.73 wouldn't make much of a differance. I need to get something in there before the snow flies within the next month so that doesn't give me time to save a bunch more money and there isn't much of a selection now but having no front diff in the middle of winters going to suck, or putting a set of diffs in, in the middle of winter sucks too.
I want to eventually go to a 3/4 ton or 1 ton setup but thats not going to be for awhile, till after these tires wear off for sure so I can get some 36s or something to compensate for the ground clearance.
Realistically I guess my diffs I want to last for 1-1 1/2 years, so if I go with 3.08 I know I won't be able to sell them in a years time, since they are useless to most people. So holding out for 3.73 would make the truck go a lot better now and I would be able to sell them when I go to 1 tons, but I have to probably change them out in the snow and that sucks.
I just don't want to be the retard who complains about 3.08s yet when they blow replaces them 3.08s again and keeps complaining, but $200 if they are 3.08s I have a completely rebuilt front and a spare rear.
Sorry there is alot of incoherent rambling going on in this post /forums/images/graemlins/rotfl.gif
Anybody want to give thier input on what I should do? /forums/images/graemlins/confused.gif
 
Since it's an '86, unless stupidly removed by a previous owner, the *stock* ratio will be on the tag there. If it comes up as "standard ratio" or something like that then you are out of luck, unless someone knows what the standard ratio is that year.

Unfortunately, destination state, vehicle weight rating, engine, tranny, and other variables governed what the vehicle got as a "standard" ratio, so even "standard" isn't something that was an across the board deal.
 
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really hate to waste a 2hr trip for nothing

[/ QUOTE ]

Rather than drive down to check have the seller pull the covers and check for you. I would be afraid to buy an axle from someone afraid of pulling the cover first (how else can you check the condition of the gears?).

I had a '84 burb with 6.2/700R4 and 3.42 axles once. It all depends on who ordered it and what they set it up with.
 
My guess would be for either 3.08's or 3.42's. 3.42 seems to be somewhat common in 6.2 trucks.
 
Thanks for the help everyone. Yeah I know what you mean about the seller not taking the covers off. I guess there probably isn't a way out of taking the covers off I will have to check the gears anyway.
3.42s wouldn't be bad either.
Wish me luck I'm heading outta town to go check. I've got a guy who wants to buy an old laptop that I bought the old lady a few years ago that will pay for the gas money either way if I decide to buy it or not.
So atleast I can check out this truck on 44s, sell a laptop and possibly buy some diffs. I'm thinking I'm going to hold out till I find 3.73s or possibly depending how bad winter gets wait till the summer and go 1 ton depending if the moneys there. I will let you know what I find out tomorrow if anyone cares /forums/images/graemlins/thumb.gif
 
40 13 was the numbers so if I am correct that is a 3.08, they have been sitting outside for the last year and the insides were filled with water and [darn].
Decided to pass and wait on some 3.73s to show up.
Thanks for the help
 
Oh yeah, score one for Shaggy! /forums/images/graemlins/tongue.gif So much for freshly rebuilt, eh? /forums/images/graemlins/smirk.gif
 
yeah... I'd would probably have to replace the axle seals at the very least then I might aswell fix my current diff if I've gotta do that.
 

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