Picked up a new rig but it has a loud bang when you take off in first

[That_4.0_ranger]

Just picked up a 1990 ford f250 with the 4.9 i6 and a 5 speed got it cheap bust has quite a few issues most concerning is that when I take off in first it makes a loud bang and you can feel it in the whole truck the faster you let the clutch out the worse it gets have no clue what it is have videos of the sound and the rearend when I take off if someone wants to see them

 

[rusty ol ranger]

Just picked up a 1990 ford f250 with the 4.9 i6 and a 5 speed got it cheap bust has quite a few issues most concerning is that when I take off in first it makes a loud bang and you can feel it in the whole truck the faster you let the clutch out the worse it gets have no clue what it is have videos of the sound and the rearend when I take off if someone wants to see them

Hows the motor mounts?

 

[RonD]

+1 ^^^

Open the hood
Start engine
Put in 1st
Foot on the brake
Let clutch out slowly and watch the engine, it should lift a little on one side, push clutch pedal down fast, listen for a "clunk", the sound of broken motor mount

Repeat test but use Reverse, engine will lift up on the other side

Slip joints on drive shafts can also make a "bang" noise if they need to be lubed
Although on 2WD trucks its usually in the tail shaft housing so not an issue

 

[rusty ol ranger]

+1 ^^^

Open the hood
Start engine
Put in 1st
Foot on the brake
Let clutch out slowly and watch the engine, it should lift a little on one side, push clutch pedal down fast, listen for a "clunk", the sound of broken motor mount

Repeat test but use Reverse, engine will lift up on the other side

Slip joints on drive shafts can also make a "bang" noise if they need to be lubed
Although on 2WD trucks its usually in the tail shaft housing so not an issue

Actually with a stick shift just watch and see if the shifter torques

 

[That_4.0_ranger]

Hows the motor mounts?

I looked at them and there pretty wore out so I’ll have to go get a new set but I didn’t think that would cause the clunk but thinking more about it that’s probably the case thank you

 

[That_4.0_ranger]

+1 ^^^

Open the hood
Start engine
Put in 1st
Foot on the brake
Let clutch out slowly and watch the engine, it should lift a little on one side, push clutch pedal down fast, listen for a "clunk", the sound of broken motor mount

Repeat test but use Reverse, engine will lift up on the other side

Slip joints on drive shafts can also make a "bang" noise if they need to be lubed
Although on 2WD trucks its usually in the tail shaft housing so not an issue

Yeah the motor mounts are shot thanks for the help

 

[That_4.0_ranger]

I looked at it and the old owner bolted a chain from the motor to the frame and I’m thinking that might be causing the bang

 

[rusty ol ranger]

I looked at it and the old owner bolted a chain from the motor to the frame and I’m thinking that might be causing the bang

Just replace the mounts lol

 

[Blmpkn]

And enjoy the free length of chain!

 

[alwaysFlOoReD]

He had it chained down because of the broken motor mount. Put in a turnbuckle and snug it up... save time and money.

 

[RonD]

The I6 engines have A LOT of torque, so do/did break motor mounts especially manual trans, they can have a very high ratio 1st gear for hauling loads and towing, often referred to as a "granny" gear, if you have that then start off in 2nd gear when unloaded, lol

 

[scotts90ranger]

For whatever reason those motor mounts are only used on 2.3L Rangers and 4.9L F series but yeah, there's nothing holding them together when they break, if it's only slamming in first since that's a low first gear ratio it's the only one with enough torque to lift the engine... those mounts are like $30, should be fairly easy to replace, when I was in an accident in November both of the mounts on my '97 Ranger gave out so the fan kissed the radiator...

 

[rusty ol ranger]

For whatever reason those motor mounts are only used on 2.3L Rangers and 4.9L F series but yeah, there's nothing holding them together when they break, if it's only slamming in first since that's a low first gear ratio it's the only one with enough torque to lift the engine... those mounts are like $30, should be fairly easy to replace, when I was in an accident in November both of the mounts on my '97 Ranger gave out so the fan kissed the radiator...

Ive only ever seen a motor mount break twice. On an an 89 150 of my buddys and one on a 93 i had for a bit. Both 300's with manuals. Maybe a running theme? Lol

 

[scotts90ranger]

Those big round mounts aren't contained and the factory ones are "hydraulic" so they're filled with oil to create kind of a shock absorber but it means only half the mount is actually holding the engine...

 

[That_4.0_ranger]

For whatever reason those motor mounts are only used on 2.3L Rangers and 4.9L F series but yeah, there's nothing holding them together when they break, if it's only slamming in first since that's a low first gear ratio it's the only one with enough torque to lift the engine... those mounts are like $30, should be fairly easy to replace, when I was in an accident in November both of the mounts on my '97 Ranger gave out so the fan kissed the radiator...

I replaced them and problem solved but I spent 57 buck apiece on them because I needed this truck asap so I couldn’t wait for rock autos shipping. Sometimes I wonder if Napa has lube for the customers if you know what I mean