CK5
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BETRAYED BY MY K5/Lazy Heffa

:haha:

A lot of guys towing with a 700R-4 don't think it's OK to let that motor spin at 2700-3000 rpm for long periods of time. Look at the factory one ton stuff, until '91 no overdrive at all, most common was 4.10's and approx 30" tires, often with a big block. 3150 rpm at 65 mph...straight from the General. You're not gonna hurt it, you probably just won't like listening to it.

Rene
 
:haha:

A lot of guys towing with a 700R-4 don't think it's OK to let that motor spin at 2700-3000 rpm for long periods of time. Look at the factory one ton stuff, until '91 no overdrive at all, most common was 4.10's and approx 30" tires, often with a big block. 3150 rpm at 65 mph...straight from the General. You're not gonna hurt it, you probably just won't like listening to it.

Rene
Yeah, I don't think high RPMs up to a point have any harmful effects on a properly built engine, or even shorten its life.
In fact, I suspect that it increases bearing life. Lugging an engine is worse on the bearings than speed.
However, it drastically increases the number of times the pistons travel up and down the bore.
But I have seen some high mileage engines that were well maintained, and had high RPMs as well as some that ran lower RPMs, and I never noticed much difference in the ridge at the top of the cylinder.

My truck, for instance, runs about 3000 rpm at 70 as it stands now, and I used it for a DD with smaller tires for many summers.
Lots of driving between 70 and 80.

I just replaced the engine at about 300k. It still had great oil pressure, and good power.
The only reason I replaced it, was because a Pep Boys water pump seized and snapped the shaft while I was heading home about 30 miles after I put it on.
The large steel fan took out both hoses and the radiator, dumping all the water out of the block in a couple of seconds.
I shut it down even before I was stopped, but the resulting heat soak warped one of the heads and I started getting a small leak into two cylinders.

I knew better than to just dress the heads on a block with that many miles. I tried to save it by carefully pulling the one head, cleaning off the old gasket, and going back on with a new one without truing the head.
I was hopeful that it was just the gasket, but no luck. Started seeping again.
I really wanted to rebuild it, but did not have the time. Truck had to roll.
So I went with a rebuilt long block.

I think I can safely say that long hours above 3K did not hurt or shorten the life of my engine.
Course it was a Ford 351, so allowances must be made......

I leave the direction of the allowances to the reader.........:whistle:
 
As mentioned, do a full fluid/filter change on the trans and cross your fingers that it lasts.

Towing in D would've helped your whole situation a ton. Deeper gears will help a ton too, don't forget that if you buy gears they will still have to be setup (shops charge $250-500 per axle, it's not a simple remove and replace deal if you don't get everything right you'll destroy the whole diff in a matter of miles) and generally you replace all the bearings/seals too which is another $100 or so per axle.

As mentioned 3/4 ton axles often have 4.10's, would be a direct swap and generally run a few hundred bucks total around here. You'd get better gearing and brakes but you'll need 8 lug wheels.

Bottom line is a K5 isn't a very good tow rig for bigger things.
 
OK, here's the updated status report.
I just got done flushing and changing the tranny fluid and filter. The fluid was in great shape, no weird smell or color, but I pulled the pan and changed it all anyway. I did an oil and filter change as well. Around 4am this morning I did a value adjustment as I thought that the valves were slapping whenever I accelerate. Turns out that the valves aren't the issue as the truck is doing the same thing after the adjustment. I believe it may be a detonation issue(pinging). Presently the timing is set to 0 but this is a rebuilt motor and I may need to advance it to help smooth out the acceleration as it sometime causes the front to bounce when I accelerate. Its definitely not a smooth deal.

I ordered 456 gears this morning and I will have them put in next friday when I get home to GA. I'm going to change all bearings and seals on the axles and the wheels as well. I dont have the budget for all this but it needs to be done. The cooling is an issue too. I just let her idle while I recharged the AC after letting out the gas this morning to do the valve adjustment (the AC line was in the way) and after the recharge letting her idle for 30 minutes with the AC on MAX causes the Temp to rise to 210 degrees. Its just too hot to let her idle with te AC on. I need to find $600 for the electric fans plus a larger Alternator.

As for it not being a towing rig, she better put out or she has to get replaced. I wont have a truck that doesnt contribute to my bottom line:mad:. So lets hope the upgrades make a difference.


As mentioned, do a full fluid/filter change on the trans and cross your fingers that it lasts.

Towing in D would've helped your whole situation a ton. Deeper gears will help a ton too, don't forget that if you buy gears they will still have to be setup (shops charge $250-500 per axle, it's not a simple remove and replace deal if you don't get everything right you'll destroy the whole diff in a matter of miles) and generally you replace all the bearings/seals too which is another $100 or so per axle.

As mentioned 3/4 ton axles often have 4.10's, would be a direct swap and generally run a few hundred bucks total around here. You'd get better gearing and brakes but you'll need 8 lug wheels.

Bottom line is a K5 isn't a very good tow rig for bigger things.
 
I don't know about the cooling, double check every thing.
If you can see the inside of the radiator through the fill hole, see if it looks clean.

Scale and other buildups with cause overheating, but when its cool, stick your finger in and wipe it around on the inside.

Lots of times on higher millage vehicles or even just the radiator, you will get a gradual build up of oil on the inside from many miles of tiny amounts of seepage through the head gaskets.
Oil in a radiator, even a extremely thin film, is devastating for cooling.

Not only is it a good insulator, but it keeps the water from wetting the metal, preventing good heat transfer.

As for the gears, just the thought of you going from 3.73 to 4.56 makes me grin.

Lots of times I make recommendations here with the thought that I just hope that helps enough for them to notice.

You might wind up not liking the gears because of engine speed, gas mileage, whatever, but the difference in off-the-line and towing performance is going to be huge.
You will love it.

Just don't let the difference in towing ability lull you into forgetting its still the same vehicle. With the same braking and weight compared to what you are towing.
 
OK, here's the updated status report.
I just got done flushing and changing the tranny fluid and filter. The fluid was in great shape, no weird smell or color, but I pulled the pan and changed it all anyway. I did an oil and filter change as well. Around 4am this morning I did a value adjustment as I thought that the valves were slapping whenever I accelerate. Turns out that the valves aren't the issue as the truck is doing the same thing after the adjustment. I believe it may be a detonation issue(pinging). Presently the timing is set to 0 but this is a rebuilt motor and I may need to advance it to help smooth out the acceleration as it sometime causes the front to bounce when I accelerate. Its definitely not a smooth deal.

I ordered 456 gears this morning and I will have them put in next friday when I get home to GA. I'm going to change all bearings and seals on the axles and the wheels as well. I dont have the budget for all this but it needs to be done. The cooling is an issue too. I just let her idle while I recharged the AC after letting out the gas this morning to do the valve adjustment (the AC line was in the way) and after the recharge letting her idle for 30 minutes with the AC on MAX causes the Temp to rise to 210 degrees. Its just too hot to let her idle with te AC on. I need to find $600 for the electric fans plus a larger Alternator.

As for it not being a towing rig, she better put out or she has to get replaced. I wont have a truck that doesnt contribute to my bottom line:mad:. So lets hope the upgrades make a difference.

A TBI motor is supposed to run around 190-210 degrees.
 
The cooling system was redone in Jan 2010, everything about my K5 gets attended to because I use her for work. The radiator and thermostat are 8mths old now. I generally redo the cooling systems on all my vehicles every summer. Now she runs normal when I drive and run the AC, but when idling for extended periods that clutch fan just doesnt cut it. I have an oil and trans cooler in addition to the AC condensor infront of the radiator. It all works great when I drive.

The towing of this little travel trailer is someting I hope she can do effortlessly once I regear and beefup the cooling. If this all fails, I'll be going back to my import trucks and giving up my 2 years dealing with domestic trucks.

I don't know about the cooling, double check every thing.
If you can see the inside of the radiator through the fill hole, see if it looks clean.

Scale and other buildups with cause overheating, but when its cool, stick your finger in and wipe it around on the inside.

Lots of times on higher millage vehicles or even just the radiator, you will get a gradual build up of oil on the inside from many miles of tiny amounts of seepage through the head gaskets.
Oil in a radiator, even a extremely thin film, is devastating for cooling.

Not only is it a good insulator, but it keeps the water from wetting the metal, preventing good heat transfer.

As for the gears, just the thought of you going from 3.73 to 4.56 makes me grin.

Lots of times I make recommendations here with the thought that I just hope that helps enough for them to notice.

You might wind up not liking the gears because of engine speed, gas mileage, whatever, but the difference in off-the-line and towing performance is going to be huge.
You will love it.

Just don't let the difference in towing ability lull you into forgetting its still the same vehicle. With the same braking and weight compared to what you are towing.
 
well thats about where she ran when I towed with her. The guage was mostly pegged at 210-230ish. Normally she doesnt run over 200 but at an idle with AC running on a hot day, she gets up to 240ish. By that time the AC becomes irrelevant. Just not enough volume to cool her down with the stock fan and all the added stuff i got infront of that.

A TBI motor is supposed to run around 190-210 degrees.
 
What kind of clutch do you have installed? sounds like a stocker of some sort, if ya dont have it already, ge a heavy duty cooling unit. I personally run one and with a new radiator, factory oil cooler and a big trans cooler, mine RARELY goes over the t-stat @ 195, and if it does, it's only like 5 degrees or so.

This was when i still lived in Phoenix,Arizona in the middle of 115* + temps during the summer months.

$600 for electric fans? you shouldn't need them in the first place.
 
Its the stock fan. I wasnt aware that there was a better alternative to that.

What kind of clutch do you have installed? sounds like a stocker of some sort, if ya dont have it already, ge a heavy duty cooling unit. I personally run one and with a new radiator, factory oil cooler and a big trans cooler, mine RARELY goes over the t-stat @ 195, and if it does, it's only like 5 degrees or so.

This was when i still lived in Phoenix,Arizona in the middle of 115* + temps during the summer months.

$600 for electric fans? you shouldn't need them in the first place.
 
for idling it will dfinately help, but also with the "severe duty" unit, it helps with those trailer pulling uphill events as well.
I just pulled a pretty decently heavy trailer from Phoenix to Indiana with my Burb and i could hear that fan engauging, or tightening up while climbing the mountain hills heading out of Phoenix when the engine started heating up, but still, it never heated up to anything more than about 215* or so.

your shroud is still intact and present too i hope?
 
Yes I have the shroud in place. Its beaten up but all there:) My temps never went above 230 but the trans did vent. After flushing and refilling today, I came to the conclusion that there was too much fluid in the trans. I had not touched it since it was rebuilt this March. It was the tranny shop that filled it. They did an awesome job on the trans becasue it should have burnt up after the abuse I put it through.

for idling it will dfinately help, but also with the "severe duty" unit, it helps with those trailer pulling uphill events as well.
I just pulled a pretty decently heavy trailer from Phoenix to Indiana with my Burb and i could hear that fan engauging, or tightening up while climbing the mountain hills heading out of Phoenix when the engine started heating up, but still, it never heated up to anything more than about 215* or so.

your shroud is still intact and present too i hope?
 
OK, here's the updated status report.
I just got done flushing and changing the tranny fluid and filter. The fluid was in great shape, no weird smell or color, but I pulled the pan and changed it all anyway. I did an oil and filter change as well. Around 4am this morning I did a value adjustment as I thought that the valves were slapping whenever I accelerate. Turns out that the valves aren't the issue as the truck is doing the same thing after the adjustment. I believe it may be a detonation issue(pinging). Presently the timing is set to 0 but this is a rebuilt motor and I may need to advance it to help smooth out the acceleration as it sometime causes the front to bounce when I accelerate. Its definitely not a smooth deal.

keep the timing at 0. its tbi, thats where it should be. the ecm adjusts it when needed. it also shouldnt ping, crappy fuel or maybe a bad knock sensor is the issue there.
 
I see the point there, if the knock sensor is bad and thus creates a knock situation, thats causing the ECM to advance the timing and resulting in the pinging. I was getting code 43 a few months ago but it stopped. Does that sound like logic?

OK, here's the updated status report.
I just got done flushing and changing the tranny fluid and filter. The fluid was in great shape, no weird smell or color, but I pulled the pan and changed it all anyway. I did an oil and filter change as well. Around 4am this morning I did a value adjustment as I thought that the valves were slapping whenever I accelerate. Turns out that the valves aren't the issue as the truck is doing the same thing after the adjustment. I believe it may be a detonation issue(pinging). Presently the timing is set to 0 but this is a rebuilt motor and I may need to advance it to help smooth out the acceleration as it sometime causes the front to bounce when I accelerate. Its definitely not a smooth deal.

keep the timing at 0. its tbi, thats where it should be. the ecm adjusts it when needed. it also shouldnt ping, crappy fuel or maybe a bad knock sensor is the issue there.
 
I see the point there, if the knock sensor is bad and thus creates a knock situation, thats causing the ECM to advance the timing and resulting in the pinging. I was getting code 43 a few months ago but it stopped. Does that sound like logic?

No.
 
Status update:

Changed fan clutch to heavy duty and noticed an immediate difference. She doesnt get hot while idling with AC on 196 degrees max. The true test will be later today when the sun is out.

Swapped in new knock sensor and reset my ECM. Took a test drive and I still have what appears to be pinging. I ran WINALDL at an idle and my knock counts is consistant 12. My BLM at idle is 108. I will log again while driving to see whats up.
 
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