Continue using RL 75w-90 in D35c rear end or switch to something else?

[Seth_TJ]

hello,

This is long but bear with me.

I am about to put a diff. guard on my rear end and change the shafts in my Dana 35c so I need to change the fluid again. The manaul recommends a API-GL5 SAE 80w-90 but I have been using the Redline 75w-90 which is acceptable (I hope

). The manaul also recommends using a 75w-140 if I you are towing (1000lb jetski/trailer) which I did all summer on the Redline 75w-90 (oops). I also have bigger tires and armor which add at least 500lbs. The oil doesn't look burnt or anything it has some black sooty looking stuff in it but it looks alright I guess, I might UOA it if I can get some extra money. I think it held up alright. Also I have 4.88 gears and a true-trac gear driven LSD.

So I need to decide now if I want to order more Redline 75w-90 or get Redline 75w-140. I can see the RL 14- robbing power from me in the winter because it will be so thick and I have the little 2.5L engine. But in the summer I probably will run a 140w.

Redline 75w-90 @ $7.00/quart
Redline 80w-90 @$7.00/quart
Redline 75w140NS @$7.00/quart

What is the difference between a 75-90 and an 80-90? My manaul says I should have been using the 80w90 but I've been using the 75w??

Now the other thing is what about the Amsoil gear lubes? Should I consider them? They have so many choices?

-What is the difference between their:

Series 2000 SAE 75W-90 @ $7.36/Quart
SAE 75W-90 Syn Gear Lube @ $7.36/Quart
SAE 85W-140 Syn Gear Lube @ $7.36/Quart

SEVERE GEAR (EP)(75W-90)@ $7.40/Quart
SEVERE GEAR (EP)(75W-140)@ $9.64/Quart


Should I just stick with my Redline or are the Amsoil lubes better?

Please let me know what you think is the correct choice for me. Let me know if you need any other information. BTW I'm in Ohio.

Thanks,
Seth

 

[sbc350gearhead]

Your manual's recommendations are for typical dino lubes. You are probably fine with the RL 75w90. If it makes you feel better, then switch to the 140. RL's gear lubes have an excellent and proven reputation. Amsoil, RP, etc will also serve your purpose.

 

[Seth_TJ]

quote:

---

Originally posted by sbc350gearhead:
Your manual's recommendations are for typical dino lubes. You are probably fine with the RL 75w90. If it makes you feel better, then switch to the 140. RL's gear lubes have an excellent and proven reputation. Amsoil, RP, etc will also serve your purpose.

---

So pretty much it doesn't matter? BTW- the dino factory fill SUCKED. That stuff was nasty. The Redline is a lot cleaner (still stinks though heh)

I was just wondering if the Amsoil severe gear was that much better or if I even needed it.


Like I said next summer when it is hot and i'm towing again I might put in a 140 for the summer. I am staying the 90w for winter though.


Still need to know the difference between a 80w90 and a 75w90?

Is the 80w90 recommendation just so it doesnt' go out of grade with Dino (too thin)?

thanks guys

 

[OiledMustangGT]

"Also I have 4.88 gears and a true-trac gear driven LSD."

Tires? .. hope it aint 33"+

if you wheel it, just get the cheapest 75w-90/ 80w-90 dino you can find. as you see, you will be popping open the diff everytime you break a shaft and/or ring gear in your case with 4.88.

just put in an 8.8/D44/ 9" and be done with it.

but if you really want to get good lube, and are easy on it you will be best off with 75W-140/ 85w-140 i have used redline and royal purple and valvoline, the only one i did not like was the valvoline (noisey)

the black stuff you saw was bearing material that has worn away over time (normal)

btw, i have a built XJ

[ October 07, 2004, 08:22 PM: Message edited by: OiledMustangGT ]

 

[OiledMustangGT]

"Still need to know the difference between a 80w90 and a 75w90? "

the 75w will flow a little better when cold. unless it gets really cold where you live or you do burnouts on a cold day as soon as you start it up, i dont see the 80w being much of a problem

 

[Seth_TJ]

quote:

---

Originally posted by OiledMustangGT:
"Also I have 4.88 gears and a true-trac gear driven LSD."

Tires? .. hope it aint 33"+

if you wheel it, just get the cheapest 75w-90/ 80w-90 dino you can find. as you see, you will be popping open the diff everytime you break a shaft and/or ring gear in your case with 4.88.

just put in an 8.8/D44/ 9" and be done with it.

---

it is a D35c with 4.88 gears, true trac limited slip, moser shaft, canyon alloys 15x8 and BFG 33x10.50 MT KM's. I haven't broke a shaft yet (knock on wood), it is a pretty good setup as far as I am concerned.

I'd like to have a TJ 44 axle that will bolt right in with 4.88's and a ARB but not enough money to get that right now.


How much thicker is a 75w140 than a 90wt? Almost twice as thick right?

 

[Seth_TJ]

I know the Mobil 1 and Redline are top tier. I don't use the Mobil since I can get the Redline cheaper SHIPPED to my door...

Really though, are the AMSOIL gear lubes really any better than the Redline stuff?

 

[OiledMustangGT]

the thicker stuff would be best, the only real difference is going to be SLIGHTLY reduced gas mileage

75w-140 vs 75w90
both flow the same when cold, the 140 will be approx 50% thicker at high temperature

no money for D44?
yes, you are past the point of no return on that D35
gears + install $300+?
trutrac $300
moser shafts $200?
diff guard $50
so you are what $850 into it by now. I could have easily scored a BUILT D44/D60 for that

I just got a geared, rebuilt D44 rear with full detroit for like $550 a couple weeks ago

[ October 07, 2004, 10:37 PM: Message edited by: OiledMustangGT ]

 

[sbc350gearhead]

I haven't seen any proof that amsoil will outperform redline. Redline gearlubes have proven themselves in high HP drag racing applications with slicks.......and it holds up fine. Amsoil will probably work just as well.......but probably not any better. The redline shockproof gear lube may be worth a look as well.

 

[Seth_TJ]

quote:

---

Originally posted by sbc350gearhead:
I haven't seen any proof that amsoil will outperform redline. Redline gearlubes have proven themselves in high HP drag racing applications with slicks.......and it holds up fine. Amsoil will probably work just as well.......but probably not any better. The redline shockproof gear lube may be worth a look as well.

---

So would Redline shockproof be about the same thing as the Amsoil Severe service extreme pressure series?

I really don't think I need that much protection. Like I said i've gotten by ok with the RL 75w90. For this winter i'm going to stick with a 75w90. Next summer when it is really hot and I am towing the ski I will switch to a 140 for a little extra security. I'll monitor my gas mileage to see if it is any different, it would a small difference i'd think. The Amsoil is also more expensive. I've got redline in the rest of the drivetrain besides the engine so I might as well just stick with what has worked great for me. Nothing against Amsoil it just seems like I get mixed signals on Amsoil and not a lot of user feedback??

 

[Seth_TJ]

quote:

---

Originally posted by OiledMustangGT:

no money for D44?
yes, you are past the point of no return on that D35
gears + install $300+?
trutrac $300
moser shafts $200?
diff guard $50
so you are what $850 into it by now. I could have easily scored a BUILT D44/D60 for that

---

I don't have a job anymore, I really have no access to money at this point. And when I did all that I didn't have enough money to do it all at once either. And the 800 is close to what I have in it. I haven't been able to find a TJ 44 with 4.88 gears and a true-trac or ARB or even open for that matter for anywhere close to that. The ones I had access to were 800 bucks for a 4.10 with a Trash-Lok. Way out of my price range at that time.

I refuse to buy anything that isn't going to bolt up. Unlike some others I find no pleasure in screwing with angles of shock mounts, spring mounts, etc and then having to weld on a tube that has bearings in it. Screw that!

The D35 has served me well so far. I actually think it isn't too bad for the 2.5L. Much rather have a 44 if I could but I don't so I live with it. Another great choice for me would have been a Super 35 but I didn't want the detroit. Now they have an ARB that would be cool