towing

[millwrightjesse]

I have a 1985 suburban 6.2 3.73 gears and a 6.2 diesel 700r4 new rebuild . And I will be moving from Moses lake WA to great falls MT. I will have a 6x12 U-Haul loaded and the suburban loaded. The trailer will be 3400 pounds loaded. Will I have any problems towing. It 480 miles over mountains

[DmaxMaverick]

No problem, if you aren't in a hurry. Take it easy and keep the tranny from "gear hunting". Keep the torque converter locked as much as possible to keep the heat down. More black smoke = more EGT = more ECT.

[Edahall]

Installing a switch to manual lock up that torque converter helps out a lot. This is one of the modifications that I did to my Suburban to keep the transmission heat down and better transmit the power to the ground. I pulled a 26 ft Airstream weighing approximately 5500 lbs. My Suburban has 3.08 gear ratios. I just kept it in 3rd gear and used 2nd gear up the hills. It worked out just fine but a little slow on the hills at higher elevation.

[More Power]

I have a 1985 suburban 6.2 3.73 gears and a 6.2 diesel 700r4 new rebuild . And I will be moving from Moses lake WA to great falls MT. I will have a 6x12 U-Haul loaded and the suburban loaded. The trailer will be 3400 pounds loaded. Will I have any problems towing. It 480 miles over mountains

I've driven that stretch many times through the years - some with a loaded truck/trailer and a naturally aspirated 6.2L and some with a 6.2TD.

When in the hills, run in direct (3rd). You'll likely be in 2nd gear on the passes at about 35-40 mph. Be patient. Keep exhaust smoke at no more than a light haze, and watch engine temperature. You should not be at full pedal. If the engine temp is above normal when you reach the top of the grades, pull over and let the temps come down a bit with the engine idling.

You should have any wind at your back while driving east. ;) Welcome to Montana.

Jim

[millwrightjesse]

Thank you. I know it wont be fast. I'm gonna have the wife go around me on lookout and have us meet at 50,000 silver dollars. Since hers is the diesel k5 with a manual transmission and it will do better on the hills

[millwrightjesse]

How do I wire in a manual lockup switch also and keep the position sensor working also?

[Edahall]

Here you go.

http://www.hotrodders.com/forum/700r4-lockup-wiring-diagram-112798.html

[DmaxMaverick]

I did the TCC manual lockup on my 85 in 1980-something. It isn't difficult.

I dropped the pan and bypassed all the gear range pressure switches, and supplied 12V to the ALDL pin (actually spliced into the harness behind the connector) via a toggle switch. At first, I used a 3 position switch, allowing for lockup with and without brake pedal interrupt (fearing a zero ground speed stall), with main power supplied with a push-pull switch mounted on the column shifter (like a 2-speed on a stick). After a week of driving, I concluded the brake interrupt was not necessary, and only used the push-pull to engage/disengage as needed. Ultimately (when the "new" wore off and I quit playing with it), I just left it "engaged" all the time, rarely ever touching the switches. The TC will unlock via the hydraulic circuit automatically, no matter what you do, as soon as the governor slows down. Also, it will not engage lock without throttle input and about 28 MPH (TV input and governor required). On 87 and earlier models, once grounding the switches on the valve body, and applying 12V to the ALDL, it is quite straight forward. However, 1-2 and sometimes 2-3 shifts can be quite hard once the fuel filter begins to restrict fuel. This is the fault of the TV sensing greater throttle input for a given power level, which increases apply pressure, making a perfect TV cable adjustment critical. A pretty good indicator of when the filter needs replacing.

I have a full diagram at the "Truck stuff pics" link in my signature. I think it's the same one I used when I did the lockup mod, as the TCC circuits are all highlighted.

[millwrightjesse]

http://i378.photobucket.com/albums/oo227/89m1007/IMG_20110505_105044.jpg
http://i378.photobucket.com/albums/oo227/89m1007/IMG_20110505_105049.jpg

[millwrightjesse]

Well I made it to great falls the suburban wanted to run 220 engine temps so I decided to put it behind the k5 I weighed the blazer and k5 it was 11500 the trailer was 4500 alone. I did notice the k5 didnt get above 200 and with the manual it did soo much better