Good night, fellow blazers, how are you all? I hope my good, I write from Spain, I have a 91 k5 blazer with 350 cid engine and th700r4 md8 automatic transmission. I have taken the automatic gearbox to repair, they have left it very well, it works great, it changes very smoothly, and everything is perfect. The only problem I have is that when starting the march, when starting from 0 miles to 10 miles both in the normal direction and in reverse, you notice a strong vibration and a scratch. This only happens when the vehicle is hot, if the engine is cold nothing happens, it is perfect, the oil that I have put on it is a dexron VI, I have changed the spreaders and the engine and gearbox studs, I am desperate for I do not know what it can be, the gearbox workshop where they have repaired it, they confirm that it is not of the change ... but I am lost, I do not know what it could be. any ideas?
CK5
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Vibration and cranck
- Thread starter Mikedohc
- Start date
Check your u joints they could be stiff until they warm up.
Your English is good, but we may be thinking different when describing noise.
Spanish may be doable for some members here. I have a co-worker who can translate anything I can't read. So if you need to give Spanish a try.
Your English is good, but we may be thinking different when describing noise.
Spanish may be doable for some members here. I have a co-worker who can translate anything I can't read. So if you need to give Spanish a try.
good night and thanks for the quick response, the noise is a little forward and a long way back, the u joint seems to be in good condition, I have greased them and they look good. It is important that it only does it hot, if it is cold everything is going great, and it is wearing dexron vi I do not know if this is important, because it is less dense than the dexron ii and it becomes more fluid ... and makes noises. the change in principle is perfect, the oil is of perfect color and good smell
Can you get a video and post it?
Hello good the video I am not able to hang it, comment that in cold everything is perfect, but perfect, as manufactured. The problem comes when it gets very hot, when you take a long trip, I think it can be: 1o.- The dexron vi oil is too liquid and hot when it is synthetic is strained by some seal. 2o.- When mounting the torque converter I put a 3 mm washer between the converter and the flywheel to adjust the measurement according to the manual, and it may be that the seal does not finish adjusting well and hot strain oil. 3o.- the ralenti or hot rpm stabilization are very low and pitch a little, it may be for this, because if you accelerate very thoroughly it does less. Any ideas?
Do you have a working lock up torque converter? Do the noise happen in all gears or just 4th?
From your description I get when you accelerate hard the noise goes away or is less?
I have not tried dexron vi in a 700r4, I use dexron III in mine.
The washers between fly wheel and torque converter is a common thing. Shouldn't be an issue as long as torque converter does not bottom out on pump.
Glad to hear from like minded enthusiast from around the world.
Check that the u bolt at rear springs are tight.
Are front hubs unlocked?
From your description I get when you accelerate hard the noise goes away or is less?
I have not tried dexron vi in a 700r4, I use dexron III in mine.
The washers between fly wheel and torque converter is a common thing. Shouldn't be an issue as long as torque converter does not bottom out on pump.
Glad to hear from like minded enthusiast from around the world.
Check that the u bolt at rear springs are tight.
Are front hubs unlocked?
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First of all I want to share with you that I am from Spain, Madrid, from where I send you a big hug, I love this car above all the cars in the world, I brought it from the USA, and I have been with it for 25 years. The vibration problem only occurs when accelerating from 0 miles to 15 miles, and it is like a scratch, it only happens when the car is very hot. then at speeds above 20 miles everything goes perfectly. I have not checked the U-joints, I will try it, it is curious that it only happens hot. From Madrid I send you a big hug, for me it is exciting to be able to talk to you and share experiences of this car, since there is nobody here who understands these cars.
It may be one of your rear brakes is dragging (not releasing fully)--if the shoes are adjusted on the tight side,they will expand from heat and cause more drag ...try feeling the rims at the lug nut area after getting the truck driven long enough to cause the noise,you may find one is too hot to touch and might be the cause..
My truck had a wheel cylinder on the right rear that was rusting up inside and not fully releasing the brake shoes ,and I'd get a low "grrrooaan" type noise out of the rear drum taking off from a stop both forward & reverse,but it sounded like it was something else in the drive line doing it like the transmission ..I feared a band or clutch in the TH400 was going out ..
One day after I drove it 25 miles I noticed an odor of burnt brake linings and I saw some light smoke coming out of the drum,the rim was very hot too..it got hot enough to make the wheel cylinder leak,and some brake fluid got on the linings--new wheel cylinders cured it..
My truck had a wheel cylinder on the right rear that was rusting up inside and not fully releasing the brake shoes ,and I'd get a low "grrrooaan" type noise out of the rear drum taking off from a stop both forward & reverse,but it sounded like it was something else in the drive line doing it like the transmission ..I feared a band or clutch in the TH400 was going out ..
One day after I drove it 25 miles I noticed an odor of burnt brake linings and I saw some light smoke coming out of the drum,the rim was very hot too..it got hot enough to make the wheel cylinder leak,and some brake fluid got on the linings--new wheel cylinders cured it..
I can tell you for sure this transmission was not made for DeX vi I am not sure if that is your problem but I rebuilt a Mitsubishi transmission and put the wrong fluid in it and it was doing the same scratch until it shifted to second gear.
Is there a difference if you take off slowly or you accelerate quickly?
