I'm worried that my TC seems to lock and unlock too much. Sometimes at steady driving it seems to randomly unlock and lock couple of times. At first I thought it was cruise control playing with throttle, but with windows up I can hear revs going up and down a tiny bit. I believe it is triggered by slight uphills, like the ones you'd normally barely notice and then continues once it is back to flat. Playing a bith with throttle makes it calm down.
I've adjusted TV cable according to the procedure which moved shift points a little up and made the shifts a bit firmer, fotunately the change is not to dramating, so I assume it was just a tiny bit too loose.
I'm worried because as with any clutch it has a limited life, so if I can make to avoid that unnecesary cycling it would be great.
The TCC can take a lot of abuse ---- up to a point. The weakest part is the sprag which can roll-over during a WOT high RPM shift -- and I've even ruined a few going for 4th/OD and when it shifted, it makes a strange 'growling" noise and then the damage is done.
It's still driveable --- just that going into L/U (TCC) it will either flare a bit, shudder or refuse to even try ... you will still have OD, but no TCC. Then it's convertor time!
If you have to use a significant amount of throttle changes to hold a highway speed and you think it's going into and out of L/U too much, you CAN drop to 3rd/Direct and that should eliminate it. BTW: 3rd/Direct will increase the RPM a bit - but you should still be able to exceed the speed limit by another 25-30 MPH or so if you live in SoCal where the limits are lower --- 'way before you hit too much RPM.
I installed a switch on my console that injects 12V directly into the transmission to make the TCC apply. I left the BOO Switch override alone so it still uncouples whenever I apply the brakes and the internal pressure sensor knows to open the circuit when the unit is below the threshold that happens in 1st/Reverse and 2nd/Intermediate.
Why does it uncouple during 2nd/Intermediate? Because if you are driving on particularly nasty black ice (in Montana, this can happen any time of the year) you can use that gear as the startup position to keep wheelspin to a minimum.
Putting the quadrant in 2nd/Intermediate gear will cause the until to hold that gear until (either)
A} you get scared or
B} the rods come out for a look at the rest of the world.
I have had to use 3rd/Direct and TCC in pulling McDonald Pass - hauling a 20' trailer with a neighbor's piano collection - and even at that altitude (mine is pre-FI, as in: a 1986 K5) and the roadspeed was still fast enough to scare me a tiny bit.
Typically I use my K5 to gather firewood and I crawl over stumps and trees with a 16' or 20' trailer behind me in the high woods here in Montana. I have a rear Gov-Lok and front Posi with 3.73:1 gears and a stroker 350/383 - which I think was a lot of money for basically just a little more torque.
I run a Crower cam, Edelbrock Low-rise manifold and a Q-Jet. I took off the computer and installed a stock HEI and still use the EGR and the AIR pump. I removed the AC 'cause this is Montana and it's not hot enough to even run it anyway.
Thoughts after 200,000+ miles in my K5 ,,,,,,,,,,,,,,,,,,
WHAT'S THE WEAK LINK ON AN '86 K5?
1. The frame is a little too flexible for me - but it is a survivor, so it's got that going for it.
2. The steering box is actually too weak for a truck of any size larger than a Toyopet (that was a real vehicle) and I've had a couple of them fail by breaking off the pitman shaft right where the splines start.
3. The Gov-lok is a weak link too - but I know that and treat it with care, making sure it knows I want it to pull with both axles --- before I actually push for too much power. You can gently "blip" the throttle --- kinda hard to explain - but it's just the way I make the clock gears move enough to apply the clutches. It takes some experience and knowing what's going on inside the differential to make it happen.
4. I wish it had had FI ... and a full serpentine belt instead of a partial serpentine belt and a PS Vee belt. The tiny AIR Pump belt is
THE 1986 OE and still running 'round and 'round!
5. The OE "Automatic Hubs" were a huge joke - unless you were a soccer mom and had to go up a slippery driveway the last 8 feet. I "ker-
BOOMED" mine about 25 years ago and went to WARN hubs. Once manually engaged, you can go from 2WD-H to 4WD-H at any time or conceivable roadspeed you want. I think. So far --- so good.
5. The electric tailgate window drive is just bad engineering. The cable driveshaft can blow up and although I've got mine sleeved and epoxied and miniature hose together clamped well -- I expect it to fail when I need it most .... again.
6. The tailgate inner panels are too flimsy to support much (read: any) weight and it will bend into the window motor --- and it can really screw things up --- it's a bad design to say the least. Don't even kneel on it --- and I'm not over 180lbs! Just sayin'
