smithoman

I've got a 92 with 330,000 on it and I'm replacing the rear diff. I also have a 5 speed manual tranny. I'm thinking of putting in Redline 75/90 G-4 in the tranny and G-5 in the differentials. I'm hoping to get better mileage, etc. Any recommendations on this? Perhaps better product with moly or ptfe? I've got a few weeks.


Also, should I get a "used" differential or put in new gears with a kit? I'm thinking new gears and kit but not sure how difficult that will be. Thanks in advance, Smitho

daved5150

iTrader: (1)

You can go to Redline's site and they will recommend oils for your specific vehicle. I like MT90 for the manual tranny...very smooth shifts. I currently have Pennzoil Syncromesh fluid in my tranny now and it's shifts smooth as butter. It's not application specific but for GM and Chrysler applications but I like the way it works in my G58 transmission. I may keep using it or go back to MT90. It only has about 5k miles on the fluid. The reason I tried is that it's designed for syncroed trannys and a friend of mine told me of guys he knew who ran it in Hondas...so I gave it a shot. I agree with GL4 fluids for the stick and yes...GL5 for the diffs. Redline is good and the well known brand Mobil 1. I haven't used Amsoil but I'm sure one of the boys will chirp in here at one point. I think synthetic is the way to go esp. in cold weather.

If you are looking to switch gear ratios, just buy a used "third" from a member here. That's where I got my 4.56's front and rear. They can take pics for you to look at and see condition of the gears. The guys I dealt with were great. Or you could post a "Want to buy" ad in the Items wanted section. Or go to a Pic n Pull...

The rear thirds are fairly simple to pull and reinstall. You have to remove four bolts on the plate that holds the axle into the axle housing itself. Slide the axle shafts out to remove/install the third. You need to remove the driveshaft off the yoke - four bolts I believe. Remove the nuts off the diff studs. Remember to drain the diff first...makes it a little lighter and cleaner to remove. Have a helper or a jack to put it on...mine fell off the jack that I tried to put it on and fortunately it fell away from me. They are heavy esp. when lying under the truck. Definitely a one or one and half banana job.

**EDIT~~ By the way, what gear ratio are you looking for??

JasonYota

iTrader: (1)

I wouldn't expect a mileage increase by switching to synthetics. I haven't on several vehicles. I run Amsoil in everything. Synthetics are good for cold flow and also good during high temps to prevent oil break down. It pays for its self just for the extended drain periods.

hyo

iTrader: (1)

definitely +1 on the MT-90 in the trans. as for the diffs i was doing some reading and alot of people say to just go with a cheaper fluid unless you never plan to take it off road. the reason behind that is because if you were to get water in your diff you wouldn't mind just flushing it out. but if you had an expensive oil you would be more hesitent