73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => 4 Wheel Drives => Topic started by: drat_bklyn on April 30, 2012, 06:49:38 pm
-
Hi all,
I'm the proud new owner of a beast (see avatar) - '86 K30, old utility truck painted flat black (with a roller) several owners back, body dents all over, but quite good for rust, and in pretty fine shape mechanically - 60k miles, carbed 350, 3 speed auto. This is my first gm experience (never had 2 keys for a vehicle before...), and you can see from my post count that I'm a newbie to the site.
I spent the weekend driving my new toy up to it's new home (heckl of an experience driving a truck like this on NYC streets, but fun), and I'm having a hard time getting the feel of the 4wd. It has WARN locking hubs, and looks like an NP205 transfer case (that's what it should have by my research, and it looks right to me - see below). I've seen the 4wd indicator light up once (must've bumped the shifter, so I took it back out), then when I was trying to get into 4wd (after locking the hubs), the indicator wouldn't come back on again. Frankly, I wouldn't expect the indicator to be 100% reliable, so I'm assuming that I can sort this out by feel. In my efforts, I'm pretty sure that I did get it into 4 low, because I could feel the higher gear ratio (whilst in reverse).
Shifter seems normal (top to bottom: 4low, N, 2high, 4high), but honestly, I coldn't tell you by feel where any of those gears are. It's sloppy side to side up and down the shifter. When I'm driving on the higway in 2wd, it's somewhere in the middle there - I don't think that I ever found neutral (but that may be a result of my lack of rigorous experimentation). I feel a bit of a click between what I assume to be 2H & N (though again, never did I press on the gas and it not move), and as I said, I'm pretty sure (but not 100%) that I got it into 4low. I couldn't find 4high - seems I push it all the way down into the seat and it just won't go. I do think that when I had the indicator on (by accident), it was because it was in 4H (whilst jimmying a carseat). But I don't think that I can put a carseat in every time that I need 4wd ;)
So, my relevant experience: '83 toyota hi-luxe. Manual hubs, with a shifter much like my K30. Pretty sure my practice in that one was to come to a complete stop before shifting (I drove that last in '90, so my memory is a bit fuzzy). '86 subaru, 4wd shifter low/high. Automatic locking hubs, and you could shift that one on the fly. Everything since then has been either full time 4wd or just 2wd.
So I'm trying to sort out feel, but once I get that, I'm also going to want to know how to drive this truck.
1. I know the 'no pavement' rule from my hiluxe, and to not drive excessively in 2wd whilst the hubs are locked
2. I'm not sure if there's a speed limit (my subaru would be comfortable at 50mph in the snow, the hiluxe less as I recall).
3. Full stop before shifting in and out of 4wd?
4. Do I correctly assume that there is a neutral hidden from me in there? When do I ever use that? When it's being towed to that big auto repair in the sky?
5. If I don't sort out the feel and the indicator doesn't work, is there any danger of driving with unlocked hubs with the shifter in 4?
6. Anything else?
Anyway, this has turned into a long post. Any help would be appreciated.
-
First off welcome to the site from California.
1. Driving on pavement with the hubs locked and the transfer case in 2h only means that you are turning the front drive shafts with out suppling power to them, so unless you want to oil everything up there is no reason to, (unless you expect to be putting it in 4wd somewhere up ahead.)
2. There are guys on here that have run their trucks up to 60 in 4h.
3. Full stop before shifting is always best.
4. There should be a neutral, if I remember right on these trucks it will not move if it is in neutral, (cuts power to both axles).
5. Again, driving with unlocked hubs and transfer case in 4wd is turning front drive shaft and front ring and pinion gears but not the axles. To lube for a short time ok, no reason to do it for extended time.
6. The indicator light should work by a switch mounted by the shifter itself, might need adjustment or rewiring or something like that .
-
Your shifter is mounted to the transmission to transfer case adaptor by one bolt which it also pivots on. Most of these have a grease fitting either in the end of the bolt, or on the shifter where the bolt goes through it. If it is shifting hard, or you have to mess with it to get it in the correct gear I would suggest greasing it, or taking the bolt out, cleaning every thing, and greasing it after re assembly. If the shifter has allot of slop in it a wave washer or two might help tighten it up.
4 lo, and 2 wheel drive are separated by neutral.
It should be a TH400 transmission.
Axles should be as long as they haven't been swapped for some reason or another. A 14 bolt full floater rear, and a Dana 60 front. Most common gear ratio is 4:10s but 4;56s are out there.
-
Thanks for the advice so far, I have some things I can check on now...
I wonder if part of my difficulty comes from the automatic transmission. All my previous experience has been with a manual - if you can't shift it, you put it in neutral and let out the clutch to spin the synchro, push it back in, and it likely solves the problem. As I said, this is an automatic (agreed, looks like a TH400), which I've never understood very well. I assume that at a full stop with my foot on the brake, the transmission is in neutral, no matter the position of the shifter. I wasn't at all focused on the transmission shifter - does that matter? Do I need to be in neutral or park or something to shift into 4wd?
Anyway, thanks again for the advice so far.
-
Welcome to the sight and mostely congradulations on owning some of the best american steel in the world... enjoy your new toy.... I just moved in to a large city with my long wheel base and it is fun to say the least but most of the little gas sippers on the road get out of the way except the ones with the coffee can exhausts..
-
They can be shifted in gear, but go allot easier in neutral.