Folks,
Did the 90k service on my '08 SR5 V6 today, and thought I'd post some results and impressions.
Because this was 90k, I needed to change the spark plugs and change the fluids in all three differentials. I've kept up with the maintenance on other things at unscheduled intervals, so air filters, chassis lube, etc. were already done earlier.
Differential Fluid Change
I bought the truck with 48k on it and had no idea the history of the differential fluids. After reading the forum for a bit, I decided to change them all at 60k and replace with Mobil 1 75w-90. Now, at 90k, I get to see the results of my maintenance.
I started at the front and worked my way back. Immediately on changing the front diff fluid, I noticed it was still markedly clear in color - looked almost like the brand new fluid I was to put in. The same thing was apparent with the transfer case. I live in PA, so we get some snow in the winters, I routinely use 4wd every month to keep the system lubed (do this if you're not!!), and use it constantly during hunting season to get to my spots. Even with all that, 30k was WAY too short an interval to change this fluid. I suppose the combination of usual 2wd driving, not really wheeling the rig, and the excellent wear characteristics of Mobil 1 gear oil added up to basically unecessary maintenance. Make it known to those in question - probably safe for 60k in the front two diffs. I might try that with the next change unless I totally chicken out and change it anyway!
The rear diff, however, was an entirely different story. Black, dirty, naaaasty fluid came pouring out when I let the drain plug go. 30k IS the right interval for the rear. No doubt about that. After the full change and a test drive, the son of a gun is QUIET on the road.
Semi-related: I can't stand the smell of gear oil. It's still stuck in my nose, and I didn't spill a drop today. :yuck:
Spark Plug Change
I changed the spark plugs at 60k last time and put in basic Denso copper plugs. I didn't want to get too fancy with the plugs just to get a baseline for performance. They worked well for 30k miles. However, a combination of internet forums, desire, and convenient coupons convinced me to go with Denso Iridiums for the 90k change. The enhanced durability and smaller electrode intrigued me. I don't consider changing the spark plugs to be an involved job but was curious to see what the "premium" plugs would do. I went with Denso Iridium Long Life plugs, model SK20HR11. The comparison with the standard plugs is apparent. I won't get into a "this sucks, that sucks, you suck" discussion on the plugs - I just wanted to try them for myself. Initial impressions on starting are a vastly smoother and quieter idle. Not sure if that's due to new plugs in general or to the Iridiums. We'll have to wait and see. Driving around in them is very, very smooth. Who woulda thunk new plugs would make such a nice difference?
More interesting were the old plugs removed from the truck. I was surprised at how dirty they were. Not having really had a lot of experience with used plugs (do lawn mowers count?), I was taken aback by the amount of fouling and oil and goo on them. Here are a few pictures. Does anyone have any observations or thoughts on the state of the used plugs? Look at the discoloration on some of the ceramic. Anybody know why that would happen? They seemed to get dirtier as they got closer to the firewall.
Did the 90k service on my '08 SR5 V6 today, and thought I'd post some results and impressions.
Because this was 90k, I needed to change the spark plugs and change the fluids in all three differentials. I've kept up with the maintenance on other things at unscheduled intervals, so air filters, chassis lube, etc. were already done earlier.
Differential Fluid Change
I bought the truck with 48k on it and had no idea the history of the differential fluids. After reading the forum for a bit, I decided to change them all at 60k and replace with Mobil 1 75w-90. Now, at 90k, I get to see the results of my maintenance.
I started at the front and worked my way back. Immediately on changing the front diff fluid, I noticed it was still markedly clear in color - looked almost like the brand new fluid I was to put in. The same thing was apparent with the transfer case. I live in PA, so we get some snow in the winters, I routinely use 4wd every month to keep the system lubed (do this if you're not!!), and use it constantly during hunting season to get to my spots. Even with all that, 30k was WAY too short an interval to change this fluid. I suppose the combination of usual 2wd driving, not really wheeling the rig, and the excellent wear characteristics of Mobil 1 gear oil added up to basically unecessary maintenance. Make it known to those in question - probably safe for 60k in the front two diffs. I might try that with the next change unless I totally chicken out and change it anyway!
The rear diff, however, was an entirely different story. Black, dirty, naaaasty fluid came pouring out when I let the drain plug go. 30k IS the right interval for the rear. No doubt about that. After the full change and a test drive, the son of a gun is QUIET on the road.
Semi-related: I can't stand the smell of gear oil. It's still stuck in my nose, and I didn't spill a drop today. :yuck:
Spark Plug Change
I changed the spark plugs at 60k last time and put in basic Denso copper plugs. I didn't want to get too fancy with the plugs just to get a baseline for performance. They worked well for 30k miles. However, a combination of internet forums, desire, and convenient coupons convinced me to go with Denso Iridiums for the 90k change. The enhanced durability and smaller electrode intrigued me. I don't consider changing the spark plugs to be an involved job but was curious to see what the "premium" plugs would do. I went with Denso Iridium Long Life plugs, model SK20HR11. The comparison with the standard plugs is apparent. I won't get into a "this sucks, that sucks, you suck" discussion on the plugs - I just wanted to try them for myself. Initial impressions on starting are a vastly smoother and quieter idle. Not sure if that's due to new plugs in general or to the Iridiums. We'll have to wait and see. Driving around in them is very, very smooth. Who woulda thunk new plugs would make such a nice difference?
More interesting were the old plugs removed from the truck. I was surprised at how dirty they were. Not having really had a lot of experience with used plugs (do lawn mowers count?), I was taken aback by the amount of fouling and oil and goo on them. Here are a few pictures. Does anyone have any observations or thoughts on the state of the used plugs? Look at the discoloration on some of the ceramic. Anybody know why that would happen? They seemed to get dirtier as they got closer to the firewall.
