oil addatives

[Fed]

I have a '91 astro with around 230k km on it and its getting a little worn. the engine is a little slugish and the transmission kind of thumps when it changes gears. I was thinking about putting this with this in the engine. And this with some DEXRON III fluid in the transmission. Also to clean the injectors some of this. So what do you guys think? Will it help a bit, or is it a waste?

Thanks in advance
-Fed

[curtis73]

Restore is one of the few brands of additives that I recommend. I used it in an Olds 307 that had a 20% compression spread between the best cylinder and the worst. After the restore it was 15%. Not a huge change, but it at least does what it says.

The Quaker State can't hurt a bit, but don't go out of your way to get it. They formulate it a tad on the thick side (still within the acceptable range for SAE standards) and give it a little extra calcium compounds to combat acids that can form from blowby that older engines can have. If you're not burning any oil then it probably won't help you too much. But like I said, it can't hurt a bit.

Fuel injector cleaner is mostly the same stuff from what I understand but I haven't done my homework.

If you're getting a thump from the tranny I would first look at two things: tranny mount, and U joints. Usually trannys don't thump, but worn mounts or u joints would. If they check out fine, you might try the additive. If your transmission is shifting fine, doesn't slip in and out of gear when sitting at a light, and you don't get excessive heat, I don't recommend any additive. But, dropping the pan, changing the filter, and adding about 5 new quarts of fluid will do wonders.

[Fed]

so i should go with what i selected and ill be ok?

[curtis73]

Yes, but I would diagnose the thumping tranny before putting any additives in it. If its an internal problem it might help, but I think its an external problem.