Tires 750 John Deere 4WD

[ncmike]

Looking at a 1984 JD750 4WD and it looks like passenger car tires on front, size 205/75 R 14 and Turf Tires 13.6 16 on the rear...will this damage the 4WD if it has been driven with this type of tires on it? Any help is appreciated and what kind of least expensive tires would you suggest? Fronts are about worn out, Thank You

 

[Karl2]

In the 80's there were several similar sized tractors that were designed to use car tires in front when rear turfs were installed, maybe the 750 is one? I don't see how this could damage the 4WD but I have been wrong before...

 

[ncmike]

Thanks Karl2, I heard that diff size tires than are called for could damage the internal workings of the front wheel drive when in 4wd but I can't see either how it could damage it.

 

[Henri88]

Hi Mike! I am by no mean an expert on the subject, but you should use the recommended tire size or at the very least the front and rear match which could be what they have . If you don't use the mfwd I can't see any problem, but as soon as you turn it on, if you don't have the right match, then you will have one set of tires turning faster then the other, putting a lot of strain on the mfwd as both front and rear traction are now connected. On slippery ground it wouldn't be so bad, but on hard dry surface.... Pretty much the same feeling as when you turn with the mfwd on, if you know what I mean. JMO. The recommended tire size for the 750 on Tractor Data are: Front 4.00-15 and Rear 9.5-24 ag tires. Good luck!

 

[RiversideProduce]

Hey Mike - I just went through tire sizing for my 790 - which i believe has the same tires as the 750. It is very important to keep the % slip within 2-5%. Which means the front tires need to spin 2-5% faster than the rears. Anything under or over that can damage the front drive. It really doesn't matter what tires they are, as long as they work together. Here is a simple formula to see if your in parameters: Front rolling circumference x MFWD gear ratio divded by rear rolling circumference. (subtract 1 x 100 = percent slip.)

 

[ncmike]

Thanks guys for your info, am still looking and hope to find it soon!!

 

[Barry 1]

The original turf tires were 25/8.50-14