tranny problem

[taurussho24v]

I have a 1990 full size blazer 350 with an auto trans i was towing a buddys conversion van for him on a tow dolly i pulled over because i didnt like the way it was towing felt like it wasnt going fast enuph and a humming noise that went away when i took my foot off of the gas pedel unloaded the van then truck goes uo to 35 miles an hour like nothing is wrong then revs as if it was in neautral if i shift it manualy 1--2--then drive it will go but gust not right. i didnt get it to go fast enuph to go into overdrive the truck has 60k origonal miles any help would be very appreciated my father gave me the truck so i gota figure it out it was in mint condition before i got it pritty much.

 

[Blue85]

First you have to post up the fluid level and fluid condition.

 

[Greg Ducato]

Most common failure on the 700R4 is the 3-4 clutch pack and 2-4 band. Trans will shift 1-2 then neutralize...

 

[taurussho24v]

tranny is full with less than 1000 miles on fluid, smells good no pices. fluid still looks fresh. would towing 4500lbs (the vans weight) a short distance burn out the 3-4 clutch set or was it just going to grenade at some other time? i would like to tow a large boat come spring. and i would also like to put a plow on it for the winter. not 4 a buissness just my driveway im just wondering on what i should have done to it when it is rebuilt. queston number 2 the van came over the dolly when i stoped the front literaly landed on the crank of the car dolly while i was stoping the truck stoped pritty short would that have anything to do with the transmission the brake light came on right after 2 no fluid leaking. brakes feel good tho.

 

[Greg Ducato]

You can tow with the 700R4 but it should be in third gear while doing so. Towing in 4th will sometimes create an overheating of the trans and the 4th gear ratio is not advantageous for pulling. There are a great many ways to fortify and modify the 700R4 for increased strength and capacity so that it is more suitable for the tasks you have planned.